# Quattro



## stumardy (Oct 25, 2009)

Hi All

Just wanted to know what people think Quattro and if its worth getting. I'm getting the S Tronic 2L tfsi. Just wanted to know what difference it would make? Heard you can slam round roundabout and from standing still to 60 is faster. Also moving off from traffic lights is quicker? 
Can anyone let me know what they think?

Thanks TT folks


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## stumardy (Oct 25, 2009)

Anyone?


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## Bayley (May 8, 2013)

Test drove both and wouldn't do without the Quattro now, especially now the nasty weather is coming.


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## relic222 (Aug 24, 2012)

It certainly offers more traction and the 0-60 times are meant to be slightly quicker. I'm not sure how quickly you pull away from traffic lights but even the FWD version should have enough grip for that... I would say definitely go for Quattro, it feels very secure when cornering, I can't say I've tried taking a roundabout at 60mph, I tend to keep my 'fast' driving out of towns...


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## Shug750S (Feb 6, 2012)

According to brochure 2l STronic, the quatro is 0.4 secs faster to 60, but 1 mph down on top speed.

Assuming anyone could notice difference or replicate these numbers on the road.


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## Bayley (May 8, 2013)

Shug750S said:


> According to brochure 2l STronic, the quatro is 0.4 secs faster to 60, but 1 mph down on top speed.
> 
> Assuming anyone could notice difference or replicate these numbers on the road.


Its handling and traction in different weather environments where I can tell the difference.


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## Hoggy (May 8, 2002)

Hi, Only driven a Mk2 without Quattro & yes front feels very light & wheels spin so easily in the wet. 
Quattro every time, especially if you are a spirited driver.  
Hoggy.


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## Patrizio72 (Mar 22, 2011)

Quattro for the win, I get enough front wheel spin from my other diesel car which does my head in.


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## leonttmk2 (Jun 22, 2012)

Go for the quattro model. The handling is superb


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## powerplay (Feb 8, 2008)

Quattro.

The end.


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## Bayley (May 8, 2013)

powerplay said:


> Quattro.
> 
> The end.


+1


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## Suzuka (Oct 15, 2012)

Bayley said:


> powerplay said:
> 
> 
> > Quattro.
> ...


To buy and Audi is to buy quattro!


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## Patrizio72 (Mar 22, 2011)

The exact reason why the car badge has four rings! if you buy non Quattro the car should be demoted to 2 rings only


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## ajayp (Nov 30, 2006)

Quattro all day, everyday.


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## moro anis (May 27, 2010)

I had a Quattro and the handling was superb.

Next was a non Quattro and it spun the wheels easily and seemed a bit more skittish but in the dry the road holding was about the same.

Now back with a Quattro and glad I've got it. Certainly worth having if you get the choice.


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## igotone (Mar 10, 2010)

200 bhp going through just the front wheels is too much. The car will drive just fine, but it's very easy to spin the front wheels from rest in the dry, let alone in the wet. In the snow and ice the car will be really challenged, especially on even moderate inclines. Quattro eliminates all the issues and is worth going for, especially if the car will be a daily driver in all weathers.


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## stumardy (Oct 25, 2009)

So I guessing the grip is really good, and less wheel spin right?

Anything I need to watch out for with Quattro?


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## moro anis (May 27, 2010)

Just remember it's still subject to the laws of physics!


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## Patrizio72 (Mar 22, 2011)

Yes but always an improvement over 2 wheels


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## SuperRS (Mar 7, 2012)

The car will feel more agile and fun to drive with fwd. however if driver enjoyment and involvement isn't that high up your list it doesn't matter. Quattro is great in the winter.

Just remember with 4wd the car uses more fuel than in fwd, and will be slower from 60mph upwards.


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## RogerB (Dec 16, 2012)

Take into account the human attitude towards the subject as well ....

Those that havn't got it ... or leastwise some, will say it doesn't matter too much. 
Those that have experienced it or who have it, wouldn't be without it.

Truth is, it works very well and is very forgiving if you make a mistake on a slippery road.
Does it mean you can drive like a whirling dervish everywhere, whatever the conditions? NO :roll:

Go over the top and you'll still go off! :lol:


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## Patrizio72 (Mar 22, 2011)

RogerB said:


> Take into account the human attitude towards the subject as well ....
> 
> Those that havn't got it ... or leastwise some, will say it doesn't matter too much.
> Those that have experienced it or who have it, wouldn't be without it.
> ...


Indeed very true but the fun part is finding where those limits are, it's good to know the limits of your stead


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## RogerB (Dec 16, 2012)

Patrizio72 said:


> RogerB said:
> 
> 
> > Take into account the human attitude towards the subject as well ....
> ...


Of course ... but the problem lies where people get to believe that having quattro and other electronic stability programs actually makes up for bad driving ... and it doesn't.
And to put any car through its paces properly you need to be able to drive, in the proper sense.
It's surprising how many don't ... and can't even control a slide or skid ... and they'll still happen with all the aids if you go over the limits.
That's the point I guess. But alas a subject on its own.


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## Patrizio72 (Mar 22, 2011)

All the technology is aimed at increasing safety and reducing the chances of coming off the road, it will eventually get to a stage where cars are self driven which will be very sad, will be very boring living in a world which doesn't have an element of human error.


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## digital_dreamer (Aug 28, 2011)

Quattro all the way yes some say it takes the fun out driving but if I wanted fun it would be a RWD M BMW for me rather a FWD car any day as I just don't class them as sports cars.


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## leonttmk2 (Jun 22, 2012)

digital_dreamer said:


> Quattro all the way yes some say it takes the fun out driving but if I wanted fun it would be a RWD M BMW for me rather a FWD car any day as I just don't class them as sports cars.


+1


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## SuperRS (Mar 7, 2012)

A car doesn't have to be a sport car to be fun. Point in case, Clio sport 172, one of the most fun cars I've ever driven on public roads, and best of all the whilst being the most fun, also the least likely to make you lose your license.

The way I see it, a fwd TT on a dry road driven hard can be a right hoot when it all comes together and it makes you smile.

The 4wd TT's don't do so as much unless its a bumpy B road, as the 4wd just turns it into a point and squirt car, not overly involving. I even found the TTRS boring after coming from a 360hp fwd 2.0tfsi as it just wasn't involving enough. The only way I truly have fun in the RS is by going very fast, and chucking power at the car.

So both have their merits.


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## stumardy (Oct 25, 2009)

digital_dreamer said:


> Quattro all the way yes some say it takes the fun out driving but if I wanted fun it would be a RWD M BMW for me rather a FWD car any day as I just don't class them as sports cars.


I agree of even, and dare I say this as I'm just about to buy my 3rd TT, a BMW Z4! It is funny tho how people without Quattro seem to slag it off tho!


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## SuperRS (Mar 7, 2012)

Who is slagging off "Quattro"?

It's not even Quattro 4wd anyway it's rebranded Haldex.


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## stumardy (Oct 25, 2009)

SuperRS said:


> Who is slagging off "Quattro"?
> 
> It's not even Quattro 4wd anyway it's rebranded Haldex.


yeah but the Haldex system is an awesome bit of kit!


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## SuperRS (Mar 7, 2012)

It's ok for the application, proper Quattro is far superior though


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## igotone (Mar 10, 2010)

There are lots of cars that are more fun and a more involving drive than the TT in any flavour - better chassis, better steering feedback, better weight distribution, but they're less than useless when the snow is on the ground. A TT with 4WD is a genuine year round all weather car and that's the main difference - you'll be driving up the inclines, while the sports cars are stuck at the bottom.


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## SuperRS (Mar 7, 2012)

If you don't fit the appropriate tyres then yes, but whilst the TT might be able get going in the snow, it won't be any better at turning or stopping than any other non 4wd car,


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## igotone (Mar 10, 2010)

SuperRS said:



> If you don't fit the appropriate tyres then yes, but whilst the TT might be able get going in the snow, it won't be any better at turning or stopping than any other non 4wd car,


No argument as regards stopping , but it will be better at turning as long as the 4WD maintains traction and you're not trying to turn at silly speeds - the laws of physics always win in the end if you're going too quick.


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## Pale Rider (Nov 15, 2011)

SuperRS said:


> It's not even Quattro 4wd anyway it's rebranded Haldex.


Meaning what? The TT Quattro system drives all four wheels and the power directed to each wheel is controlled by computer, so if one wheel is slipping it'll redirect the power to a wheel that isn't. In what way is that not proper 4wd?


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## Patrizio72 (Mar 22, 2011)

My TT is the most fun car I have ever had but my previous cars weren't exactly inspirational!


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## Patrizio72 (Mar 22, 2011)

SuperRS said:


> The 4wd TT's don't do so as much unless its a bumpy B road, as the 4wd just turns it into a point and squirt car, not overly involving.


Is this how you treat your women too? lol


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## igotone (Mar 10, 2010)

Patrizio72 said:


> My TT is the most fun car I have ever had but my previous cars weren't exactly inspirational!


LOL- the danger is you jump into a Boxster S or a Nissan 370Z and try to drive it the same as your TTRS you'll come unstuck pretty rapidly. The TTRS isn't a tail out drifting car, it's a great combination of power and safety which is pretty unique. Sure- all that power is fun, but it will never have the fun factor of a powerful RWD sports car - even if the RS is quicker - which it will be in many cases.


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## Patrizio72 (Mar 22, 2011)

igotone said:


> Patrizio72 said:
> 
> 
> > My TT is the most fun car I have ever had but my previous cars weren't exactly inspirational!
> ...


When it came to buying the RS I was close to going for the 370Z instead, it was a toss up between the two


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## igotone (Mar 10, 2010)

Me too actually - the 370Z was on the short list - but that was when I bought my first TT.

When you look at the practicality of the TT though , it's 4WD, all weather ability and enormous storage space with the rear seats folded, it's a tough act to follow in a performance package.


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## Patrizio72 (Mar 22, 2011)

Yes it certainly is a brilliant all rounder, even with the point and squirt driving :lol:


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## SuperRS (Mar 7, 2012)

Pale Rider said:


> SuperRS said:
> 
> 
> > It's not even Quattro 4wd anyway it's rebranded Haldex.
> ...


1 where did I say its not proper 4wd? I said its not proper Quattro. Big difference. And Haldex can't send power to each wheel seperately, and at most it will always be a 50/50 split. Quattro is much more dynamic in that sense as it can shift more than 50% of the power to rear, and does so more quickly. It's just a much better 4wd system, trouble is it won't work with transverse engine layouts like in the TT. The tt can't even do 4wd engine breaking like the Quattro unless you modify the Haldex with a competition controller


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## Patrizio72 (Mar 22, 2011)

That's why the 'Quattro' is a completely different car


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## powerplay (Feb 8, 2008)

I guess that's why on the previous (and best) Audi Quattro concept car which used the TTRS 2.5, it was mounted longitudinally and therefore presumably used a Torsen 4WD drivetrain.


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## Patrizio72 (Mar 22, 2011)

powerplay said:


> I guess that's why on the previous (and best) Audi Quattro concept car which used the TTRS 2.5, it was mounted longitudinally and therefore presumably used a Torsen 4WD drivetrain.


That's pure rally car driving


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## SuperRS (Mar 7, 2012)

powerplay said:


> I guess that's why on the previous (and best) Audi Quattro concept car which used the TTRS 2.5, it was mounted longitudinally and therefore presumably used a Torsen 4WD drivetrain.


Indeed, that car would have awesome dynamics with the latest Quattro with sport diff!


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## Pale Rider (Nov 15, 2011)

SuperRS said:


> 1 where did I say its not proper 4wd? I said its not proper Quattro. Big difference. And Haldex can't send power to each wheel seperately, and at most it will always be a 50/50 split. Quattro is much more dynamic in that sense as it can shift more than 50% of the power to rear, and does so more quickly. It's just a much better 4wd system, trouble is it won't work with transverse engine layouts like in the TT. The tt can't even do 4wd engine breaking like the Quattro unless you modify the Haldex with a competition controller


Quattro is just an Audi marketing name for their 4wd drive cars AFAIK and they call their Haldex-equipped cars "Quattro", so it is a Quattro.

Also I think the TT system can send more than 50% of the power to the rear wheels. I haven't found the figures anywhere (maybe in the KB somewhere) but I've read several posts claiming it does. Where's your source for saying the TT is limited to 50/50?

You say it can't "send power to each wheel separately". Possibly not but doesn't the electronically controlled differential address this?

As for "engine breaking (sic)" so what. That's what brakes are for. Turbo engines don't have much braking anyway.


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## drjam (Apr 7, 2006)

Pale Rider said:


> SuperRS said:
> 
> 
> > 1 where did I say its not proper 4wd? I said its not proper Quattro. Big difference. And Haldex can't send power to each wheel seperately, and at most it will always be a 50/50 split. Quattro is much more dynamic in that sense as it can shift more than 50% of the power to rear, and does so more quickly. It's just a much better 4wd system, trouble is it won't work with transverse engine layouts like in the TT. The tt can't even do 4wd engine breaking like the Quattro unless you modify the Haldex with a competition controller
> ...


Yep, quattro is just their blanket marketing term - from the horses mouth: http://www.audi.co.uk/audi-innovation/our-technologies/quattro.html
So the haldex system is certainly "proper quattro"; it's open to debate and personal opinion whether people regard it as "proper 4wd" (I tend to describe our TT, several generations old as it is, as "temporary 4wd").

Personally I think it's worth having for all-weather traction/safety, though a 2wd on winter tyres will be safer in cold/icy conditions than a quattro on summers. (I've never put winters on the TT and it's got round fine for the past 13 years; though I do recall a couple of (not) stopping moments! 
And maybe for trying to put down big power if you insist on booting it from scratch to race from the lights (not my thing, so don't know).
"Handling" though is pretty subjective, e.g. some people like their cars to "drive like its on rails" (seems to be a common phrase on here), some don't. 
And IME anyway it's less to do with simply which wheels are being driven, more to do with a bunch of other factors: chassis, weight & weight balance, suspension set-up, tyres... 
So I've driven both 2wd and other 4wd cars which, imo, have been more fun to drive, but many more that have been worse. 
But as a quick, all-conditions A-to-B machine, I've never had any complaints (even on our old, slow, oft-criticised version) - hence it's been kept so long. If I was buying an Audi again, I'd certainly try to afford the quattro again.


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## SuperRS (Mar 7, 2012)

Pale Rider said:


> SuperRS said:
> 
> 
> > 1 where did I say its not proper 4wd? I said its not proper Quattro. Big difference. And Haldex can't send power to each wheel seperately, and at most it will always be a 50/50 split. Quattro is much more dynamic in that sense as it can shift more than 50% of the power to rear, and does so more quickly. It's just a much better 4wd system, trouble is it won't work with transverse engine layouts like in the TT. The tt can't even do 4wd engine breaking like the Quattro unless you modify the Haldex with a competition controller
> ...


Wrong wrong wrong wrong.

Proper Quattro is exclusive to Audi. Haldex is what every Tom dick and Harry can run. Want Haldex, and you can buy a car from several different manufacturers with the same tech. It's not real Quattro. Sorry but that's reality.

And no Haldex can't do more than a 50/50 split, and the Haldex TT's don't even make use of an electronic diff either. It can brake wheels individually under a ESP condition though.

As for engine braking, it's a very good tool for scrubbing speed, and one of the reasons why the original Audi Quattro excelled so much under braking.....


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## igotone (Mar 10, 2010)

I'm not sure about this 50/50 split thing which keeps getting quoted..

From Audi's own web site....

quattro®: Assured cornering, superb control

A car such as the Audi TT RS Coupé needs special treatment to put its power to the road. Enter quattro, Audi's renowned four-wheel-drive technology. With quattro, optimal drive delivery to each wheel is managed automatically and continuously, for superior handling and phenomenal grip - even in less than perfect driving conditions.

In 1980, the Audi quattro was the first permanent four-wheel drive production car. So while the technology is thoroughly tried and tested, it has also been enhanced and evolved ever since it was first introduced.

More grip, more driving enjoyment

*In addition, the quattro drivetrain has been upgraded for the TT RS allowing, if necessary, 100% of the power to be guided to the front or rear wheels. This enables you to make the most of the car's incredible torque by, for instance, pulling out of bends even sooner.*


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## powerplay (Feb 8, 2008)

Two facts that I am aware of:

With the Haldex system, there is a single clutch connecting the transmission to the rear wheels, there is not a separate clutch connecting the transmission to the front wheels - these are permanently driven - therefore the power split can vary from F100%:R0% (clutch fully open) to F50%:R50% (clutch fully closed).

Audi use the term "Quattro" for all 4WD cars, regardless of the physical mechanism whether Torsen or Haldex; "Quattro" is not a name specifically aimed at the Torsen coupling only.

A lot of marketing blurb is written by people that make assumptions!!

Note that Haldex is not bespoke to Audi and is also the 4WD coupling used in vehicles such as the Bugatti Veyron and Lamborghini Aventador.


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## Pale Rider (Nov 15, 2011)

SuperRS said:


> Wrong wrong wrong wrong.
> 
> Proper Quattro is exclusive to Audi. Haldex is what every Tom dick and Harry can run. Want Haldex, and you can buy a car from several different manufacturers with the same tech. It's not real Quattro. Sorry but that's reality.
> 
> ...


The Haldex is "Quattro" because Audi call it "Quattro" - there's a badge on the back. You may choose to define it differently but it's Audi's marketing term. You're not Humpty Dumpty by any chance?

Where's the source for this 50/50 split limit? And where's the source of your claim that Haldex TTs don't use an electronic differential? And who says that engine braking is "one of the reasons why the original Audi Quattro excelled so much under braking"? Engine braking is pretty insignificant compared to what modern brakes can do.


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## brittan (May 18, 2007)

The term 'quattro' as applied to any Audi 4WD system should be spelt with a lower case q and was taken from the company name 'quattro GmbH'.

The original Audi Coupe with 4WD transmission was the Audi quattro; now often known as the Ur-quattro.

The layout of the TT front drive arrangement or 'bevel box' is shown below. As you can see, drive to the front wheels cannot be disconnected or reduced in any way and 4WD is achieved by adding or subtracting torque to the rear wheels via the Haldex unit. 


The TT has Electronic Differential Lock (EDL) which mimics the function of a limited slip diff while using a normal open differential. If one front wheel spins (on ice perhaps) relative to the other front wheel the system detects this imbalance via the ABS sensors and brakes the spinning wheel thus transferring torque back across the diff to the wheel with the better grip.
EDL is only fitted to the front diff/wheels.


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## RogerB (Dec 16, 2012)

To add my two penneth ... as I've mentioned in other posts, a number of years ago, involved heavily in Rallysport, I owned a number of Deltas, the last one an Integrale, transverse engine, manual 5 speed box, and all wheel drive, permanently driven using Torsen differentials. Lancia's beat-all Delta that won several rally championships.
Even for then, it was quick and sure-footed, top responsive on full boost pressure and easily hung on to any type of road surface.
I now drive a 3.2TT as an every day car with quattro, and if I'm honest I'd be hardpressed to tell the difference in road-holding, allbeit I don't put the TT down any forest tracks.

Split hairs all you like, but when you've had both, you know. And as I said somewhere around the front of this thread, those that decry quattro, will be probably those that either don't have it, nor do they want it ... for reasons of their own.

Audi's quattro system being electronic suffers no time lag whatsoever, according to the techo stuff, and is designed primarily to do 2 things, one save fuel when its not operating, and two provide 4 wheel drive in adverse conditions.

In my book, that's an advancement on mechanical torsen diffs. and permanent AWD.


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## ChadW (May 2, 2003)

RogerB said:


> To add my two penneth ... as I've mentioned in other posts, a number of years ago, involved heavily in Rallysport, I owned a number of Deltas, the last one an Integrale, transverse engine, manual 5 speed box, and all wheel drive, permanently driven using Torsen differentials. Lancia's beat-all Delta that won several rally championships.
> Even for then, it was quick and sure-footed, top responsive on full boost pressure and easily hung on to any type of road surface.
> I now drive a 3.2TT as an every day car with quattro, and if I'm honest I'd be hardpressed to tell the difference in road-holding, allbeit I don't put the TT down any forest tracks.
> 
> ...


This is the best post I have read about quattro 4WD. Superb. 8)


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## Pale Rider (Nov 15, 2011)

brittan said:


> The term 'quattro' as applied to any Audi 4WD system should be spelt with a lower case q and was taken from the company name 'quattro GmbH'.


Whenever I type Quattro in on this site it upshifts the q. It just did it again - can't be bothered to retype it.


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## SuperRS (Mar 7, 2012)

powerplay said:


> Two facts that I am aware of:
> 
> With the Haldex system, there is a single clutch connecting the transmission to the rear wheels, there is not a separate clutch connecting the transmission to the front wheels - these are permanently driven - therefore the power split can vary from F100%:R0% (clutch fully open) to F50%:R50% (clutch fully closed).
> 
> ...


In the veyron and Lamborghini Haldex is used in reverse though! Which is good!


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## Patrizio72 (Mar 22, 2011)

many moons back my brother had a Lancia Delta and boy was that a fun car even as a passenger, will always be one of my favourites


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## SuperRS (Mar 7, 2012)

Pale Rider said:


> SuperRS said:
> 
> 
> > Wrong wrong wrong wrong.
> ...


So because marketing men say so, it must be true....

Haldex isn't real Quattro. Sorry. Otherwise every other Haldex car is also "Quattro" and that is just stupid isn't it.

But if you buy so heavily into marketing be my guest, but a real Quattro car with the torsen 4wd like fitted to the b7 rs4 drives very different to Haldex 4wd. You feel the difference the most when launching and hitting corners. Torsen 4wd ie real Quattro feels alot more mechanical, more immediate. And less of the "confused" feeling you get with Haldex at time as it struggles to decide where to put its power at times.

Real Quattro is far far far superior to Haldex, and only a fool will think otherwise....

The fact you consider engine braking insignificant shows you know next to nothing on the subject of performance or track driving. 4 wheel engine braking gives hugeeeeee advantages, you could have atleast googled it first before making yourself look like a fool


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## RogerB (Dec 16, 2012)

Patrizio72 said:


> many moons back my brother had a Lancia Delta and boy was that a fun car even as a passenger, will always be one of my favourites


It was fun to drive, and often quite hairy especially in the forest ... as the Delta had a tendency to over-steer on light gravel or stony roads. There was a technique used to get round bends at full chat, using a quick flick to get the back end out, and steer back in to the exit and straighten up still on full boost pressure and away to the next.
Whereas, as we all know TT understeers.
I also remember, a while before that seeing for the first time on its debut the works Audi Quattro with Michel Mouton at the controls on the Lombard RAC, and when you compared rear wheel drive cars, like Escorts and suchlike .... the driving style was totally different, and did give the impression the Quattro "ran on rails". Simply because it didn;t go around corners tail out on full opposite lock like a Ford Escort Twincam would do.
But strangely later on as stated that became the way to drive the Delta, regardless of AWD.

Much was learned by others from the likes of Juha Kankkunen, Henri Toivenon with AWD in the early rallysport AWD era, but to my mind later on the master was Colin McRae. RIP

See how many "flicks" you can spot. :twisted:


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## powerplay (Feb 8, 2008)

SuperRS said:


> Haldex isn't real Quattro. Sorry. Otherwise every other Haldex car is also "Quattro" and that is just stupid isn't it.
> 
> But if you buy so heavily into marketing be my guest, but a real Quattro car with the torsen 4wd like fitted to the b7 rs4 drives very different to Haldex 4wd. You feel the difference the most when launching and hitting corners. Torsen 4wd ie real Quattro feels alot more mechanical, more immediate. And less of the "confused" feeling you get with Haldex at time as it struggles to decide where to put its power at times.
> 
> Real Quattro is far far far superior to Haldex, and only a fool will think otherwise....


IMO quattro is whatever Audi says it is, it matters not what implementation of 4WD. quattro is just an Audi brand name, it is not "a 4WD system" in itself.

Which is better - Torsen or Haldex - is obviously down to personal opinion, and if you think it's better to have drive sent to both axles permanently then you will prefer Torsen over Haldex!

Another thing to note is that the Torsen system used in the [proper :wink: ] Audi quattros is not bespoke to Audi any more than Haldex is or isn't; Torsen (from Torque Sensing) is used by many other manufacturers including Toyota's Supra, Volkwagen's Passat, Pontiac's Firebird, even a Pug's 405!

Which is clearly stupid :roll: 



SuperRS said:


> In the veyron and Lamborghini Haldex is used in reverse though! Which is good!


Yes indeed! They are permanent rear wheel drive, with up to 50% of power possible to the front wheels.


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## drjam (Apr 7, 2006)

powerplay said:


> SuperRS said:
> 
> 
> > Haldex isn't real Quattro. Sorry. Otherwise every other Haldex car is also "Quattro" and that is just stupid isn't it.
> ...


Exactly. 
Not sure why this is proving so hard to understand... :?


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## Pale Rider (Nov 15, 2011)

drjam said:


> powerplay said:
> 
> 
> > SuperRS said:
> ...


I know what you mean. I queried SuperARS's statement that:

"It's not even Quattro 4wd anyway it's rebranded Haldex."

because it didn't make any sense to me. I just wondered what he meant. Apparently he's just a brick short.


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## SuperRS (Mar 7, 2012)

powerplay said:


> SuperRS said:
> 
> 
> > Haldex isn't real Quattro. Sorry. Otherwise every other Haldex car is also "Quattro" and that is just stupid isn't it.
> ...


This isn't 100% correct and I will explain later when on a PC.

Haldex still isn't Quattro, marketing men can say what they want.


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## igotone (Mar 10, 2010)

What's surprising is how little we know for sure about these 4WD systems and the lack of available information at consumer level.


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## SuperRS (Mar 7, 2012)

I blame the marketing men who are clever with their words in deceiving consumers!

To compare Haldex to Quattro is an insult


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## igotone (Mar 10, 2010)

I've lost count of the car reviews I've seen quoting the 50/50 distribution for the TTRS when Audi quite clearly state it can deliver 100% power to either the front or rear wheels if necessary. I can't imagine Audi getting away with telling porkies on that scale. I'm sure I've read that the TTS also is capable of delivering more than 50% to the rear wheels. I dunno about the rest of the range, but given the collective knowledge on this board, I think we're woefully uninformed about the true capabilities of these systems.


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## powerplay (Feb 8, 2008)

I think I remember seeing a good explanation on a site a while back, can't recall at the moment, but there is a big difference depending on if you are torqueing about power split or power delivery (see what I did there?  )

The Haldex can split the power a maximum of 50:50. It is not physically possible for it to work any other way - the front axle is **permanently** connected and the rear axle is driven by a power take off from the front axle. Once the Haldex clutch is fully engaged, you cannot "reduce" the power going to the front axle - the clutch can't be more than 100% engaged :roll: :lol:

However, a TTRS will still *deliver* 100% (or as near to 100% as makes no difference) of the torque to the rear wheels if the fronts are both on ice or if you lift the front wheels completely off the ground.

Hopefully that makes sense?


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## brittan (May 18, 2007)

Yee Haa: ^^ Someone who understands and can explain it well; as opposed to spouting with certainty but out of one's aRSe.


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## igotone (Mar 10, 2010)

powerplay said:


> I think I remember seeing a good explanation on a site a while back, can't recall at the moment, but there is a big difference depending on if you are torqueing about power split or power delivery (see what I did there?  )
> 
> The Haldex can split the power a maximum of 50:50. It is not physically possible for it to work any other way - the front axle is **permanently** connected and the rear axle is driven by a power take off from the front axle. Once the Haldex clutch is fully engaged, you cannot "reduce" the power going to the front axle - the clutch can't be more than 100% engaged :roll: :lol:
> 
> ...


Perfect sense! [smiley=thumbsup.gif]


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## SuperRS (Mar 7, 2012)

brittan said:


> Yee Haa: ^^ Someone who understands and can explain it well; as opposed to spouting with certainty but out of one's aRSe.


So do you now know the difference between real Quattro and Haldex????


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## relic222 (Aug 24, 2012)

For what it's worth I remember being told - I believe on this forum - that the TTS and TTRS have a newer version of the Haldex system than the TT Quattro (or quattro). I believe the TT has a gen 2 Haldex system and the TTS has gen 4 which I presume would result in slightly different effects.

Also, after just having a quick read on Wikipedia (take all facts with a pinch of salt) it says that the TTRS has 'a specially adapted version of the latest generation multi-plate clutch from Haldex Traction' although it doesn't go into detail. The source for the sentence is this webpage http://www.audi.co.uk/about-audi/latest ... eneva.html but it only talks about the torque split which has already been explained.


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## SuperRS (Mar 7, 2012)

The TTRS is gen 4 as you say.

Saab had a superior version of the Haldex during the time or even before the TTRS was in production.

Quattro allowed

For permanent 4wd (with front rear split ratio as required)
4 wheel engine braking (very important for stability)
Equal length shafts within its drivetrain for feel, less vibration and no/less
Torque steer.
Fully mechanical with no electronic input
Compact
Superior off road and in the snow to Haldex.
Robust
Can powerslide and oversteer
Layout was/is unique to Audi.
Will only work with longitudinal mounted applications

Haldex (when fitted to front engined cars)

Is mainly fwd
Will overheat/fail if forced to drive all 4 wheel continuously under hard driving
Can get confused on higher power applications as it tries to decide where to send power
Defaults to understeer
Is good for economy
Is cheap to utilise
Works with transverly mounted engines
Not unique to Audi/vag
Electronically controlled 
Not as robust as mechanical 4wd (real Quattro)


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## powerplay (Feb 8, 2008)

Clearly then you're referring to "true" quattro being the torsen mechanical diff.

Certainly, this was the first 4WD system used by Audi - although they didn't invent it, the idea originated as far back as 1958 from Vern Gleasman and was first used by Audi in in 1986.

Note that Audi were not the first to use this system, it was in use since 1983 in the AM General High Mobility Multi-purposed Wheeled Vehicle.

It is not bespoke or only used by Audi, Toyota introduced the Torsen diff in 1989, Mazda in 1991 and Rover in 1994.

All the companies called it something different; Audi called it quattro, but it's not unique to Audi and is no different to Haldex in that regard.


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## brittan (May 18, 2007)

The main difference between Gen 2 and Gen 4 is that on Gen 2 the hydraulic pressure to close the clutch is generated by differential speed between input and output of the Haldex unit. Hence the front wheels MUST spin before the rear wheels receive torque.

The Gen 4 unit has an electric pump to generate the hydraulic pressure to together with an accumulator to provide instant pressure/flow from that reserve. Hence the Gen 4 unit can react pro-actively to throttle position rate of throttle application (amongst other inputs) and do not require the front wheels to spin before delivering torque to the rear wheels.

There's more info on all things Haldex in the Knowledge Base Tech section.


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## BigAardvaark (Mar 5, 2012)

There's no "proper" or "real" quattro. They're just different.

:roll:


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## SuperRS (Mar 7, 2012)

powerplay said:


> Clearly then you're referring to "true" quattro being the torsen mechanical diff.
> 
> Certainly, this was the first 4WD system used by Audi - although they didn't invent it, the idea originated as far back as 1958 from Vern Gleasman and was first used by Audi in in 1986.
> 
> ...


No torsen isn't unique, VW had 4wd cars long before Audi made the Quattro for example. This isn't my argument.

It's the packaging, the compactness, which made it unique. The fact it was coupled to turbocharged engine is what rose the Quattro name to fame.

Haldex just isn't true Quattro, it just I'm essence alone is completely different


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## brittan (May 18, 2007)

BTW, in its first few years of manufacture, the original road going Audi quattro did not have a Torsen centre differential, just a normal open diffs with a manual locking arrangement on the centre and rear ones - first cable operated and later vacuum operated.
The Torsen centre diff was not fitted until late 1986.


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## SuperRS (Mar 7, 2012)

BigAardvaark said:


> There's no "proper" or "real" quattro. They're just different.
> 
> :roll:


Yes they are different.

Haldex is Haldex

Quattro is Quattro.

It wasn't until the mk1 TT and mk1 Audi A3 that the waters where muddied with this inferior system and marketing excerise.

Real Audi fans have never considered Haldex as Quattro.

But in the TT world of yuppie posers who have no real long term admiration for the brands technical excellence Haldex is deemed as Quattro.

It's funny because when you go on the golf GTI or Cupra forums, people there will also say that Haldex cars are not Quattro.

Guess the Audi marketing guys have done their job well, atleast in the TT land.

If we had this same discussion over on the rs246 forums they would all agree with me.

But then again when it comes to performance, mods, and heritage TT owners here have always been weird compared to other performance VAG forums.


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## rustyintegrale (Oct 1, 2006)

I think all cars in this country should have some form of auto quattro. Period.

Even if it's not 'quattro' in the way the purists would consider it, there is no doubt Haldex can keep an average driver out of trouble.


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## SuperRS (Mar 7, 2012)

Also makes one wonder why the Audi Quattro Concept, designed to celebrate 30 years of Quattro uses guess what REAL Quattro.

Why go through all that effort of mounting the 2.5tfsi longitudinally otherwise, if it wasn't for the fact that its superior and sticks to heritage??!!


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## BigAardvaark (Mar 5, 2012)

SuperRS said:


> BigAardvaark said:
> 
> 
> > There's no "proper" or "real" quattro. They're just different.
> ...


Yep, :roll:


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## relic222 (Aug 24, 2012)

SuperRS said:


> BigAardvaark said:
> 
> 
> > There's no "proper" or "real" quattro. They're just different.
> ...


Love it. Try to insult as many people as you can in one post :lol: I don't consider myself an Audi fan, I love my car but have not real brand loyalties to Audi, guess that leaves me as a yuppie poser


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## powerplay (Feb 8, 2008)

Just out of interest, here is an extreme situation test of the Audi Q5 "quattro" which uses the "proper" torsen system.





And here is how a BMW X3 handles the same test with a Haldex-type system. A Haldex quattro (cough) would behave similarly.





You don't need to speak German to understand what they think of Torsen vs Haldex, Lol.


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## ChadW (May 2, 2003)

SuperRS said:


> BigAardvaark said:
> 
> 
> > There's no "proper" or "real" quattro. They're just different.
> ...


Apparently there are two types of internet forum Troll, the half hearted ones who see the light and not get into an abusive argument with people after so many bans, the Haldex Troll if you like and then there are the original proper full strength Trolls who are so far up themselves that they should really be an MP of some sort, if not already. The Torsen Troll if you will, evenly distributed abuse to all corners at all times. :roll:


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## SuperRS (Mar 7, 2012)

powerplay said:


> Just out of interest, here is an extreme situation test of the Audi Q5 "quattro" which uses the "proper" torsen system.
> 
> 
> 
> ...


Oh yes the typical BMW marketing video that only a fool wouldn't see through . Already been well discussed and well rubbished for donkeys years on forums

I can post similar videos of real world scenarios of real Quattro dominating other 4wd cars up a snowy hill!!!


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## powerplay (Feb 8, 2008)

SuperRS said:


> Oh yes the typical BMW marketing video that only a fool wouldn't see through . Already been well discussed and well rubbished for donkeys years on forums


Lol, hook, line..!

Yeah I know this is deliberately biassed bmw crap, the Q5 had it's traction control disabled, otherwise it would have braked the spinning wheels and the torsen dif would have worked.

But it does show that on it's own, with no other aids, the Torsen dif has limitations when one side has zero traction.

I'm still scratching my little yuppie head over the phrase "quattro is quattro". Of course quattro is quattro.

My TT is quattro; that's not my designation, Audi stuck the badge on it, not me.


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## SuperRS (Mar 7, 2012)

Marketing men fool me daily too.
A badge makes all the difference.

If I scribble prince William on my forehead does that make me the future king?


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## powerplay (Feb 8, 2008)

SuperRS said:


> Marketing men fool me daily too.
> A badge makes all the difference.
> 
> If I scribble prince William on my forehead does that make me the future king?


No.

But if the Queen scribbled it, then I dunno, maybe! :lol:


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## SuperRS (Mar 7, 2012)

Serious question.

Would the TTRS be a better sports car with Haldex or proper Quattro?


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## powerplay (Feb 8, 2008)

SuperRS said:


> Serious question.
> 
> Would the TTRS be a better sports car with Haldex or proper Quattro?


I think that's one of those "it depends" situations, and I assume you meant to type Haldex or Torsen :wink: (or maybe Haldex or original quattro)?

If I used the TTRS in competition and frequently raced then Torsen would probably provide a better driving experience.

If however like the majority of TT owners I rarely or never used the car in that regard but instead just enjoyed it as a fast, enjoyable road car, then Haldex probably makes the most sense, providing 4WD where I'll benefit the most with assuredness during inclement weather, the best traction to make use of the engine's power and the best economy for that 90% of the time when 4WD is not actually required.


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## drjam (Apr 7, 2006)

SuperRS said:


> Serious question.
> 
> Would the TTRS be a better sports car with Haldex or proper Quattro?


Serious answer:

As - other than in your head - there's simply no such thing as "proper quattro" (because quattro is just a term used however they see fit by those cunning & tricky marketing types who own it as a trademark), that question doesn't even make sense. 
On the other hand, had you asked "Would the TTRS be a better sports car with a Haldex or a Torsen-based system?" then it would be the basis of an interesting and sensible debate about the different systems' technical and driving merits. Which - thank God - has sort of been happening in parallel on this thread.

It's still incredible that so far you haven't proven able to separate fact (which is that Audi own the term quattro and can use it how they want: e.g. see link I posted earlier where they say what it covers) from opinion (yours being that one type of quattro system is better than the other, which is fair enough but irrelevant to what is and isn't called quattro).
You can keep calling people "fools" and being "deceived by marketers" as much as you want, but it's you that doesn't seem able to understand a very, very simple concept.


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## Chris Woods (May 12, 2013)

This is cracking me up

As far as audi see it

Torsen = quattro

Haldex = quattro

They named the systems the same ,one may be inferior in your opinion or it may even have been proven to be inferior but the fact is they are both quattro

Even If you think different lol


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## SuperRS (Mar 7, 2012)

So when stasis/Revo sell their big brake kits, which are brembo/Alcon calipers, with the brembo/alcon logo removed and replaced with stasis/Revo, does that no longer make them brembo/Alcon? But instead a stasis product? (Even though they have had no design or technical input into the brake system?)

Like I've said and is generally consensus everywhere but the TT forum, Quattro is deemed to be what it solely was until 1998.

Even car mags don't refer Haldex to being proper Quattro.

From a TTRS point of few, if it had a traditional and proper Quattro system it would be much more highly regarded as its dynamics would be much improved.

I'd rather go sideways under power than straight on. We can leave that to playschoolers.

Suppose I will just need to step up from the TT next time round and leave this wet wipe handling to you pansies


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## SuperRS (Mar 7, 2012)

Chris Woods said:


> This is cracking me up
> 
> As far as audi see it
> 
> ...


What if I told you Walter rohlr himself says Haldex isn't real Quattro....then what, and he's the godfather of Quattro :-*


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## Patrizio72 (Mar 22, 2011)

To Quattro or not to Quattro, that is the question...


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## Pale Rider (Nov 15, 2011)

SuperRS said:


> What if I told you Walter rohlr himself says Haldex isn't real Quattro....then what, and he's the godfather of Quattro :-*


Then I'd ask you to provide a link - but I've done that with a lot of your other claims and you haven't provided any supporting evidence.

I'd also question your claim that the TT quattro "Is mainly fwd". I have never seen anything that supports this claim, although some people - mainly those who are trying to rubbish it - say this. True front wheel drive cars wear out their front tyres far quicker than their rear tyres, but the TT quattro seems to wear its tyres relatively evenly - in my experience. This suggest to me that it's NOT mainly fwd.


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## SuperRS (Mar 7, 2012)

You aren't hitting those corners fast enough then, you straight line warrior!!

It's pretty clear from the diagrams that the car is mainly fwd, but some people will believe marketing instead of looking at the technical diagrams.

It's fwd till slip is detected. Therefore mainly fwd.

A Porsche turbo kills its rear tyres before its front tyres, as that has more rear bias


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## powerplay (Feb 8, 2008)

I would agree a TT quattro is more front than rear biased, both my current RS and previous S wore the fronts more than the rears, although the difference was far far less than in my previous FWD only cars - probably only 1mm of tread depth difference.

From this I would deduce that despite being front-biased, the rears are being used far more than you might think and that this statement


> It's fwd till slip is detected. Therefore mainly fwd.


 is applicable to the older Haldex technology only and does not apply to the current quattro cars.

As mentioned previously, the GenIV and now GenV Haldex has progressively improved to allow electronic operation rather than just mechanical operation upon loss of traction; my TTRS sends power to the rear very often and mainly due to throttle and steering input, not just because of front wheelspin, which happens only rarely!


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## SuperRS (Mar 7, 2012)

The faster you go the less power gen 4 Haldex sends to the rear.
Under ESP conditions the Haldex clutch releases and you have a 2wd car!!!

True Quattro is superior in so many ways


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## stumardy (Oct 25, 2009)

SuperRS said:


> The faster you go the less power gen 4 Haldex sends to the rear.
> Under ESP conditions the Haldex clutch releases and you have a 2wd car!!!
> 
> True Quattro is superior in so many ways


What gen is the new 2L TFSI cars say a 13 plate?


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## powerplay (Feb 8, 2008)

SuperRS said:


> The faster you go the less power gen 4 Haldex sends to the rear.
> Under ESP conditions the Haldex clutch releases and you have a 2wd car!!!
> 
> True Quattro is superior in so many ways


Could you post a link to the documentation that explains this?


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## Pale Rider (Nov 15, 2011)

powerplay said:


> SuperRS said:
> 
> 
> > The faster you go the less power gen 4 Haldex sends to the rear.
> ...


+1. You got there before me.

It's OK to post your opinions, SuperRS, but don't try to pass them off as fact.

My 13MY TDi is wearing out all the tyres pretty evenly so - I'm guessing - that the rear wheels are doing a fair proportion of the driving. Unlike you, I don't necessarily think that this is a good thing. You have a simplistic notion that RWD is good and FWD is bad but I don't share that. Provided that the 4WD kicks in when it's needed (i.e. when the front wheels are slipping) that's OK by me. Having driven various FWD, RWD and mid-engine cars I've come to the conclusion that RWD (front-engine)is the worst for road driving, given modern technology.

You seem to have missed the fundamental point that the only advantage of 4WD is that it provides more traction. That's it. It can alter the handling, of course, but that's not of much interest nowadays - you can alter the handling of the car more accurately using the various computer stability programs that are now commonplace.


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## SuperRS (Mar 7, 2012)

powerplay said:


> SuperRS said:
> 
> 
> > The faster you go the less power gen 4 Haldex sends to the rear.
> ...


It's in one of the other threads on this website I forgot where I found the info and tbh I've lost interest in this topic now.

As for the ESP bit that might even be in the manual.

I think I read it in the Audi TTRS self study guide they give to their techies for both counts.


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## SuperRS (Mar 7, 2012)

Pale Rider said:


> powerplay said:
> 
> 
> > SuperRS said:
> ...


Ok that explains alot, you drive a TDI, at the power level Haldex does the job fine. I'm talking 420+ bhp cars here.


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## rustyintegrale (Oct 1, 2006)

Wow this really has hit a nerve hasn't it?

First it's 'quattro' with a small 'q' as you will note from the badges affixed to all 'quattro' cars marketed by Audi.

Second the term 'quattro' refers to all-wheel drive systems fitted now or previously to Audi vehicles.

Third, the original 'quattro' system is derived from that fitted to the Iltis - a military vehicle developed by the Volkswagen Group of which Audi is a part. This system allowed the engine's power to be delivered to all four wheels permanently.

The Ur quattro was similarly based but used the Torsen torque sensing system to allow torque to be delivered to individual axles as driving conditions determined. The advantage the Torsen system has over the more recent Haldex is in it's 100% mechanical function. It does not require electronic data provided by wheel speed sensors and is known as a proactive system whereas the Haldex and other viscous coupling systems are known as reactive because they only redirect torque after wheel slippage is detected. The advantage of this is only really noticeable in hard driving where the Torsen system delivers a seamless transfer of torque from one axle to the other.

Torque split between wheels on the same axle is an evolution of the quattro system and can be controlled by a manual locking differential or as more recently witnessed, through the use of electronics.

Audi presumably went in to rallying in order to develop their four wheel drive system for use on road cars. In it's early incarnations it was comparatively basic only delivering power to two axles in varying percentages. As the quattro system was developed and the split between wheels on the same axle became feasible then the manual control of this required a lot more driver skill.

Electronics has allowed similar technology to be applied to ordinary road cars and made the benefits of all wheel drive available to all. You only have to witness the chaos after a snowfall in the UK to know that all wheel drive in whatever shape or form gives a huge advantage over front or rear wheel driven cars.

So 'quattro' now is a marketing tool. Like 'GT' it is a way of separating the base models from the premium models in their fancy clothes. It is also, in my view, a technological marvel that should be fitted as standard to all cars, not just Audis.


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## brittan (May 18, 2007)

I've posted some of that already but on a couple of points:

The Ur quattro did not have a Torsen centre diff from inception: it had normal open diffs with mechanical locking arrangements on the centre and rear diffs; cable operated at first and later vacuum operated. 
The Torsen centre diff wasn't fitted until late 1986.

The Gen 4 Haldex does not require front wheel slippage to generate the hydraulic pressure to engage the clutch, hence it can be deployed in a pro-active fashion.


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## brittan (May 18, 2007)

SuperRS said:


> powerplay said:
> 
> 
> > SuperRS said:
> ...


I can't find anything that specifically says _"The faster you go the less power gen 4 Haldex sends to the rear."_ however during steady state cruising conditions very little torque is required at the rear axle and the Haldex clutch would be effectively open. That would be the same irrespective of the actual cruising speed. 
Press the accelerator pedal rapidly in these conditions and (some) torque would be sent to the rear.

The Haldex clutch is opened when:
1. ESP active
2. ABS active
3. Brake light switch 'ON'
4. Handbrake (switch) 'ON'

The lack of a centre differential forces the programming of these actions.


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## SuperRS (Mar 7, 2012)

4 more scenarios which show true Quattro is far superior


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## illingworth22 (Sep 6, 2011)

and here's me, just back from Spain, thinking quattro was Spanish for four :wink:


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## brittan (May 18, 2007)

Spanish - cuatro
Italian - quattro

Their pronunciation is almost identical and both mean four - but I expect one is real, and/or far superior. :wink:


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## Chris Woods (May 12, 2013)

SuperRS said:


> Chris Woods said:
> 
> 
> > This is cracking me up
> ...


Walter rohlr can say what he wants , I said audi named them the same , which they did , regardless of what Walter thinks.

Walter clearly wasn't in the marketing department ....


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## stumardy (Oct 25, 2009)

So guys it worth getting then? along with the DSG gearbox it should move?!


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## SuperRS (Mar 7, 2012)

Yeah and a remap to bring it alive


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## SuperRS (Mar 7, 2012)

Chris Woods said:


> SuperRS said:
> 
> 
> > Chris Woods said:
> ...


And marketing can say what they want....


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## Pale Rider (Nov 15, 2011)

stumardy said:


> So guys it worth getting then? along with the DSG gearbox it should move?!


The thing to remember about 4WD is that it gives you better traction - and that's all. It doesn't improve cornering, although it can alter handling, and it obviously doesn't improve braking. So it gives you an advantage in conditions of low grip (like snow) or where you're applying more power than two wheels can put down (which is quite easy with 200bhp). Where traction control would intervene and cut power on a FWD car the quattro can use all the power so you can accelerate more quickly.

Coupled with the S-Tronic gearbox's seamless changes its does make for a surprisingly fast car off the line, even in feeble 170 bhp TDi form.


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## igotone (Mar 10, 2010)

Pale Rider said:


> stumardy said:
> 
> 
> > So guys it worth getting then? along with the DSG gearbox it should move?!
> ...


Of course it does....

*Basically, 4WD does not introduce power oversteer. However, most people still prefer it simply because it provides superior cornering grip thus improve cornering speed. As I have promised earlier in the Cornering Grip section, here I'll explain how 4WD improve cornering grip :
Consider a driving wheel running in a corner. Due to the frictional force applied from the road surface, the tread in the contact patch distorts and creates slip angle. The faster the car corner, the more centrifugal force generates thus the larger the slip angle becomes. You can interpret this as the elastic distortion of the tyre generates a counter force to keep the car fighting with the centrifugal force. When the car is accelerated fast to the extent that the elasticity of the tyre reaches its limit, it could not distort anymore, thus more speed will lead to the tyre slide, and the car lose grip. This point is what we call "Cornering Limit".*

*A FWD or RWD car has already a lot of tyre distortion (slip angle) in the driving wheel because the tractive force is shared by only two wheels. Therefore there is not too much space left before the tyres running into their cornering limits. On the contrary, 4WD cars distribute tractive force to all wheels, thus each wheel shares considerably less tractive force thus create smaller slip angle in cornering. The car can corner at higher speed before the slip angle reach the cornering limit.*


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## SuperRS (Mar 7, 2012)

TDI's aren't fast. They just feel brisker than they are.


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## Pale Rider (Nov 15, 2011)

igotone said:


> Pale Rider said:
> 
> 
> > stumardy said:
> ...


Where does this quote come from? It doesn't seem to make a lot of sense - it would be interesting to know who wrote it.

There's no argument that 4WD changes the handling - for better or worse depending on your point of view - or that 4WD can generate more centripetal force in a corner when the car is being drifted, so that the driving wheels are effectively pulling the car round a corner, but that's not usually the fastest way around a corner except on slippery surfaces.


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## RogerB (Dec 16, 2012)

Actually, it does ....

Slip angle characterisitics and tyre performance is well documented, and known well to those that are qualified.

Tyre mechanics is actually a complex subject, as is traction on differing surfaces under varying conditions, where weight, force, inertia and tractability is concerned. It's nothing new, it's been around for years.

And why group B rally cars in the eighties adopted four wheel drive, or if you want AWD, in an effort to put power down effectively. In real terms it wasn't possible on 2 wheels and car control was nigh impossible ....

Latterday four wheel drive, whether Torsen mechanical or electronic aided Haldex systems are designed to cater for both traction in poor conditions and maintain an element of over-all fuel efficiency in these days of frugal fuel usage, by only coming in to use when needed.

http://www.tiretechnologyinternational. ... BlogID=850


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## igotone (Mar 10, 2010)

Pale Rider said:


> stumardy said:
> 
> 
> > So guys it worth getting then? along with the DSG gearbox it should move?!
> ...


Of course it does....

*Basically, 4WD does not introduce power oversteer. However, most people still prefer it simply because it provides superior cornering grip thus improve cornering speed. As I have promised earlier in the Cornering Grip section, here I'll explain how 4WD improve cornering grip :
Consider a driving wheel running in a corner. Due to the frictional force applied from the road surface, the tread in the contact patch distorts and creates slip angle. The faster the car corner, the more centrifugal force generates thus the larger the slip angle becomes. You can interpret this as the elastic distortion of the tyre generates a counter force to keep the car fighting with the centrifugal force. When the car is accelerated fast to the extent that the elasticity of the tyre reaches its limit, it could not distort anymore, thus more speed will lead to the tyre slide, and the car lose grip. This point is what we call "Cornering Limit".*

*A FWD or RWD car has already a lot of tyre distortion (slip angle) in the driving wheel because the tractive force is shared by only two wheels. Therefore there is not too much space left before the tyres running into their cornering limits. On the contrary, 4WD cars distribute tractive force to all wheels, thus each wheel shares considerably less tractive force thus create smaller slip angle in cornering. The car can corner at higher speed before the slip angle reach the cornering limit.*[/quote]

Where does this quote come from? It doesn't seem to make a lot of sense - it would be interesting to know who wrote it.

There's no argument that 4WD changes the handling - for better or worse depending on your point of view - or that 4WD can generate more centripetal force in a corner when the car is being drifted, so that the driving wheels are effectively pulling the car round a corner, but that's not usually the fastest way around a corner except on slippery surfaces.[/quote]

The quote came from here....

http://www.autozine.org/technical_schoo ... ling_5.htm

If you do a search though you'll find plenty of support for the principle elsewhere.


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## Pale Rider (Nov 15, 2011)

igotone said:


> The quote came from here....
> 
> http://www.autozine.org/technical_schoo ... ling_5.htm
> 
> If you do a search though you'll find plenty of support for the principle elsewhere.


I thought it came from something like that. They're basically conflating two different effects. The interesting bit in that link is at the end:

"*In the past 2 decades, tyres of sports cars had been widened for about 50%, in addition to the growth in diameter, the contact patch area had been largely increased. Of course this is intended to increase the grip. However, increased contact patch area means every square inches of the contact patch carries less cornering force, so the tread distort less and the slip angle is reduced.**It is known that for the range of slip angle we concern (normally less than 20°), tractive force has less influence to the narrow slip angle than the wide slip angle. *"

You may notice the giveaway in the final sentence "tractive force" - that's where 4WD has a big advantage.

It's simple physics. Basically when a car goes round a corner it has to generate a centripetal force (not centrifugal as mentioned in that article which is in the opposite direction). There are fundamentally two ways that this can be done:

1. It can rely entirely on the lateral grip of the tyres. When the car's front wheels are turned they generate a force that causes the car to change direction. This happens even if the car is in neutral - i.e. freewheeling
2. It can rely on the engine power - its "tractive force". In this case the trick is to set the car up to be pointing into the corner that you're going round. Having done that the centripetal force can be generated by applying engine power using the longitudinal tyre grip. The front wheels are no longer generating a lateral force, mainly because they're probably no longer pointing into the corner - they may even be pointing out of the corner (opposite lock).

When you're going round a corner you can rely on either of these two effects, or probably a combination of the two. However, the quickest way round a corner depends on the level of grip that the tyres have got. It's pretty obvious that rally cars use option 2 most of the time, and it's also pretty obvious that F1 cars use option 1, except when they get it wrong.

It's also pretty obvious that modern cars have so much tyre grip on a decent road that no one goes round a corner in a "drift". That's why 4WD doesn't give better cornering power for road use.


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## RogerB (Dec 16, 2012)

You were doing pretty well up until you stated that:

"It's also pretty obvious that modern cars have so much tyre grip on a decent road that no one goes round a corner in a "drift". That's why 4WD doesn't give better cornering power for road use. "

Which doesn't even make sense, nor does it equate ..... however,

This ... RWD versus 4WD
Basically, 4WD does not introduce power oversteer. However, most people still prefer it simply because it provides superior cornering grip thus improve cornering speed. As I have promised earlier in the Cornering Grip section, here I'll explain how 4WD improve cornering grip :

From the same site different section ... read on.

http://www.autozine.org/technical_schoo ... ling_5.htm


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## Pale Rider (Nov 15, 2011)

RogerB said:


> You were doing pretty well up until you stated that:
> 
> "It's also pretty obvious that modern cars have so much tyre grip on a decent road that no one goes round a corner in a "drift". That's why 4WD doesn't give better cornering power for road use. "
> 
> Which doesn't even make sense, nor does it equate ..... however,


Because you didn't understand what I said doesn't mean that it doesn't make sense. And when you say "it doesn't equate" what is that meant to mean? Equate to what? This is not an equation.

I'll put it more simply. The only way that 4WD gives better cornering power than 2WD is when you're using the engine's traction to drive you round the corner - i.e. when you're drifting it. This is not a fast way of getting round corners on a normal road (or a track) so 4WD doesn't increase cornering power in road use. It's obviously a very different matter if you're rallying - when the lateral grip of the tyres is very low it's very much faster to use this technique and 4WD cleans up.

Basically a 4WD TT wouldn't beat a 2WD drive TT round, say, the Nurburgring. On a rally course it would leave it standing.

And that link has already been posted.


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## RogerB (Dec 16, 2012)

"It's also pretty obvious that modern cars have so much tyre grip on a decent road that no one goes round a corner in a "drift". (non lunatic drivers don't tend to on public highways)

"That's why 4WD doesn't give better cornering power for road use. "

Tell me how sentence 1, relates and proves sentence 2.

That's what doesn't equate .... no proof, no maths, merely your opinion. (and apparently nobody else's)

As for the post being posted previously, what can you say ? ..... twice then, and you still don't get it. :lol:

No good knockin ''.... etc etc....

Like I stated at the begining of this thread, there will be non quattro drivers who will de-cry it.

I wish I could forecast six numbers for Friday's lotto the same. :roll:


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## Pale Rider (Nov 15, 2011)

RogerB said:


> "It's also pretty obvious that modern cars have so much tyre grip on a decent road that no one goes round a corner in a "drift". (non lunatic drivers don't tend to on public highways)
> 
> "That's why 4WD doesn't give better cornering power for road use. "
> 
> Tell me how sentence 1, relates and proves sentence 2.


I thought I explained that very clearly and simply. The link that you quoted (and another person) is talking about how 4WD provides better cornering power when the tyres are slipping. It explains that this is due to the tractive force of the engine being used to drive the car round the corner. It also explains that when wider more grippy modern tyres are used the slip angle is decreased and 4WD is not so advantageous.

In simple terms - that you might possibly, just, understand - it's talking about the use of "power oversteer". If you'd ever driven on a rally track you'd be familiar with the technique of setting the car up for a corner by turning the car into the corner and pressing the throttle to throw the rear out. You then use the power of the engine to drive you round the corner - you don't use the lateral grip of the tyres at all. When you're using the engine's power to take you round the corner on a slippery surface 4WD roughly doubles your centripetal force relative to 2WD.

In road use, on dry grippy surfaces, absolutely no one drives like this - so 4WD doesn't improve cornering power.

There are plenty of articles about this on the net - here's a simple one for you:

http://www.autocar.co.uk/blogs/anything ... eral-drive
‎


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