# What speed in each gear



## MosTT (Nov 25, 2009)

Hi people ,this might sound like a stupid question but what sort of speeds should you reach in each gear 225 TT .


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## T3RBO (Dec 9, 2003)

Same as any other car really...

Can't say I ever look at my rev counter when driving as gear change is all down to car noise and experience

Many, many many years ago my driving instructor told me that 1st is 1000 revs, 2nd 2000, 3rd 3000 etc


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## Guest (Jun 2, 2010)

Data from the electronic workshop manual except 176 kW/6-speed (sales brochure supplement). See attached MS Excel 2003 spreadsheet.

132 kW/5 speed
······················Cog 1···Cog 2····Ratio·······Overall
Final drive I···63·········15·········4.200·······N/A
Final drive II··63·········19·········3.316·······N/A
1. gear··········42·········11·········3.818·······16.036
2. gear··········40·········19·········2.105·······8.842
3. gear··········39·········29·········1.345·······5.648
4. gear··········35·········36·········0.972·······4.083
5. gear··········32·········33·········0.970·······3.215
6. gear··········N/A·······N/A·········N/A·········N/A

132 kW/6 speed
······················Cog 1···Cog 2····Ratio·······Overall
Final drive I···63·········15·········4.200·······N/A
Final drive II··63·········19·········3.316·······N/A
1. gear··········41·········12·········3.417·······14.350
2. gear··········40·········19·········2.105·······8.842
3. gear··········39·········29·········1.345·······5.648
4. gear··········38·········33·········1.152·······4.836
5. gear··········35·········30·········1.167·······3.868
6. gear··········32·········33·········0.970·······3.215

165 kW/6 speed
······················Cog 1···Cog 2····Ratio·······Overall
Final drive I···63·········15·········4.200·······N/A
Final drive II··63·········19·········3.316·······N/A
1. gear··········41·········12·········3.417·······14.350
2. gear··········40·········19·········2.105·······8.842
3. gear··········39·········29·········1.345·······5.648
4. gear··········37·········34·········1.088·······4.571
5. gear··········34·········31·········1.097·······3.637
6. gear··········31·········34·········0.912·······3.023

176 kW/6 speed
······················Cog 1···Cog 2····Ratio·······Overall
Final drive I···N/A·········N/A·········4.235·······N/A
Final drive II··N/A·········N/A·········3.273·······N/A
1. gear··········N/A·········N/A·········3.357·······14.217
2. gear··········N/A·········N/A·········2.087·······8.838
3. gear··········N/A·········N/A·········1.469·······6.221
4. gear··········N/A·········N/A·········1.088·······4.608
5. gear··········N/A·········N/A·········1.108·······3.626
6. gear··········N/A·········N/A·········0.912·······2.985

(final drive ratio x gear ratio) /engine speed in rps = wheel speed in rps
(wheel rps x tyre circumference in metres) / 1000 x 3600 / 1.6093 = road speed in miles per hour

[EDITED calculation 15th February 2011 for 165 kW 6-speed car running 225/40/R18 tyres at 637 mm diameter. Spreadsheet updated]

1st gear @ 6,500 rpm = 33.8 mph
2nd gear @ 6,500 rpm = 54.8 mph
3rd gear @ 6,500 rpm = 85.9 mph
4th gear @ 6,500 rpm = 106.1 mph
5th gear @ 6,500 rpm = 133.4 mph
6th gear @ 6,500 rpm = 160.4 mph

Doug


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## MosTT (Nov 25, 2009)

Ok thanks I only ask because when I pull away fast 1st and 2nd gear don't seem to do much then 3rd gear kicks in and it flys .just wondering is this the norm for turbos ? .


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## T3RBO (Dec 9, 2003)

Turbo should kick in around 2 to 3000 revs if that helps mate


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## Guest (Jun 2, 2010)

Depends what the engine speed is when you change up and what level of boost is being delivered in your car at that speed. If it is of any interest, I ran a check on my commanded and delivered boost using the Liquid TT gauge to see if there was anything untoward. This is a full wide-open throttle run from about 1,000 rpm to 6,500 rpm.

viewtopic.php?f=2&t=163417&hilit=boost+graph&start=60#p1744596

Doug


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## Fictorious (Sep 15, 2009)

MosTT said:


> Ok thanks I only ask because when I pull away fast 1st and 2nd gear don't seem to do much then 3rd gear kicks in and it flys .just wondering is this the norm for turbos ? .


The time it takes for the turbo to spool up you'll have hit redline in 1st and be well on your way in second, could be why?


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## a19arf (Nov 5, 2009)

when i,m travelling quickly i prefer to look where i,m going not what revs i,m doing :lol:


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## Guest (Jun 2, 2010)

Fictorious said:


> The time it takes for the turbo to spool up you'll have hit redline in 1st and be well on your way in second, could be why?


Sounds good to me. I agree, you're not likely to be lingering long enough in 1st or 2nd gear to feel the boost. Try a wide open throttle run from 1,000 to 1,500 rpm right through the rev range on a quiet straight flat piece of road - same conditions as for a data logging run and you'll be able to get a feel for when the boost comes on.

Also, try changing down accidentally from 6th to 2nd at 50 mph for an overtaking manoeuvre instead of 6th to 4th and see what that feels like. Tell you what, don't bother. I did it the other week and you don't wanna go there! Thankfully the engine survived my misdemeanour to contest another traffic light grand prix. :wink:

Doug


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## paul4281 (Jan 25, 2010)

1st - 2nd - 3rd dont bother lookin @ rev counter, if u ovr takin go 6th 2 3rd thn change b4 the red line :!:


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## MosTT (Nov 25, 2009)

Doug Short said:


> I found this on an internet somewhere for the 225 PS car:
> 
> Final Drive - 3.316:1
> 1st Gear Ratio - 3.417:1
> ...


So doug are you saying you can be doing 62.8 mph in 2nd gear ?


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## Fred (Jan 7, 2010)

The figures are wrong, it only does about 56 in 2nd (and thats like the 7k rev limit or whatever it is, not 6)

I'm sure the box some how has a 2nd final drive for 5th and 6th as well so that needs taking into account.


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## Guest (Jun 3, 2010)

Fred said:


> The figures are wrong, it only does about 56 in 2nd (and thats like the 7k rev limit or whatever it is, not 6). I'm sure the box some how has a 2nd final drive for 5th and 6th as well so that needs taking into account.


Let's see a corrected calculation then Fred. That was a 'back-of-envelope' estimate based on second-hand data I got on the web. I tried it with 225/40/ZR18 which come out at 637 mm diameter and that gives more gear down so the speeds go up.

I don't see why it looks wrong because the top speed of the cars is limited to 155 mph and I'm estimating 7 mph shy of that in 6th with rpm to spare to the red line, so it looked reasonable to me.

Doug


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## Fred (Jan 7, 2010)

Not having a go, just pointing out they are wrong so we need to change how its worked out.

I dont have time right now but there are some apps on the internet that will make this a lot easier.


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## Guest (Jun 3, 2010)

No worries Fred! I'd just rather people had some data prepared if they're going to challenge rather than just saying it's wrong with no further qualification when it's only meant to be an estimate for guide purposes. 

I do recall reading something in a late 80s/early 90s Observers' Guide book by Stuart Bladon [excellent tomes] that explained that the reason they started quoting 0-80 mph times was that it (a) gave a better handle on an engine's flexibilty and (b) was fairer because a lot of cars even at that time could reach 100 km/h or 62 mph in 2nd gear (i.e. so a further gearchange up to third wasn't required and thus they could 'unfairly' perhaps post a marginally higher sprint time.

It's all small beer in the end and sadly for me, although I enjoyed working up the calculation, it didn't get to the heart of the question in this instance.

Doug


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## Fred (Jan 7, 2010)

Just worke it out (using a util) and your numbers are correct.

The gear ratios they are based on therfore must be wrong. When I say wrong I mean the two final drive ratios are doing something we arnt taking into account and the actual ratio we are using is wrong.


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## Guest (Jun 3, 2010)

O.k. then, so methodology correct but something slightly amiss at the final drive stage.

I remain broadly happy with the data (BTW I cross-checked the 225 PS data with an official-looking source) so I look forward to you working out what the subtle difference is! 

Doug


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## Fred (Jan 7, 2010)

I dont know how I'm going to work it out to be fair. I dont understand how the two final drive ratios work with each other.

You (we) have 63mph @6000 and it 100% doesn't do 60 in 2nd, not even bouncing off the limiter.


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## Guest (Jun 3, 2010)

O.k., I'll keep searching for an explanation. It would be nice to resolve it. I took the term 'final drive' to mean exactly that. Final. 

Does this diagram help Fred? Both front and rear bevel gears are a 1:1 ratio (17:27 x 27:17 = 1.00) so no extra gearing effect there.










1 - Engine 
2 - Clutch 
3 - Manual gearbox 
4 - Input shaft 
5 - Output shaft for 5th/6th/reverse gear (pinion shaft II) 
6 - Output shaft for 1st-4th gear (pinion shaft I) 
7 - Differential 
8 - Bevel box 
9 - Propshaft 
10 - Haldex coupling 
11 - Rear final drive 
12 - Differential 
I - 1st gear 
II - 2nd gear 
III - 3rd gear 
IV - 4th gear 
V - 5th gear 
VI - 6th gear 
R - Reverse gear 
A - Final drive 
T - Speedometer drive 
W1 - Front bevel gears 
W2 - Rear bevel gears

Doug


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## Fred (Jan 7, 2010)

Not sure I'm clever enough to work it out to be honest, maths is not my strong point. I will keep looking though.

If it helps as a check the speed in gear at 6000 is pretty much...

1 - 29 mph
2 - 56 mph
3 - 75 mph
4 - 97 mph
5 - 125 mph

Cant confirm 6th but I bet its about 145 mph


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## Guest (Jun 3, 2010)

O.k., me again.

I think I have worked out what the subtle difference should be. See how there are two 'final drive' ratios? I think one is for the output shaft for 1st-4th gears (pinion shaft I) and the other for the output shaft for 5th/6th/reverse gear (pinion shaft II). So I've used 4.200 for pinion shaft I and 3.316 for pinion shaft II. That gives:

[EDIT: see revised earlier post for revised calculations with correct tyre sizes for all engine & gearbox variants]

Good challenge Fred. What do you reckon? I've updated the original calculation with manufacturer's data from the workshop manual so we can be absolutely certain the gear ratios are correct.

Doug


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## Fred (Jan 7, 2010)

That looks more like it. So much so I reckon they are spot on!


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## Guest (Jun 3, 2010)

Phew! We got there in the end and I've learnt a bit more about gearboxes and final drives. [smiley=book2.gif]

What's tomorrow's lesson Fred? This is one heck of a lot cheaper than the Open University (so I hear). :wink:

Doug


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## Fred (Jan 7, 2010)

Optimum shift points? BHP vs Torque? 225 vs V6? Debunking of the quattro makes you corner faster myth?


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## Guest (Jun 3, 2010)

Fred said:


> Optimum shift points? BHP vs Torque? 225 vs V6? Debunking of the quattro makes you corner faster myth?


Power vs torque sort of done here:
viewtopic.php?f=8&t=172194&hilit=+torque#p1754123

[EDIT 16th February 2011] Optimum shift points now evaluated here:

viewtopic.php?f=2&t=192361&start=10

225 vs V6 done to death and I don't want to be murdered by resurrecting it again. Best of all is a turbo V6 conversion. Quattro makes you corner faster? More likely to be mainly due to weight balance effect on inertial forces and mechanical grip offered by tyres.

This feels like "Ask Elvis" now. :lol:

Doug


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## Fred (Jan 7, 2010)

"Quattro makes you corner faster? More likely to be mainly due to weight balance effect on inertial forces and mechanical grip offered by tyres"

Indeed, but the amount of people who think they can go around a corner faster because of 4wd is alarming.

If anything its slower as like for like you have more weight to contain.


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## MosTT (Nov 25, 2009)

Ok thanks for that ! phew that was hard work .


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## Guest (Jun 3, 2010)

MosTT said:


> Ok thanks for that ! phew that was hard work .


No, not hard work, just fun fun fun 'til daddy took the TT away.

Depends how you get your kicks I suppose. :wink: A traffic light grand prix here, a gear ratio calculation there...

Doug


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## nate42 (Apr 9, 2008)

Great post!

Typo in your excel on cell B7, should be 1.097 not 0.970, that ruins the calculations for the 5th gear so worth mentioning (not trying to be a smart ass).

Is the gear box really different on QS? Why?

Ignore the above I noticed that you corrected the excel while I was writing that.


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## Gazzer (Jun 12, 2010)

lost on first three posts and the rest fried the remaining brain cell hiding behind left eye ball......so sitting cabbage faced and staring blankly till i recover wd guys lol


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## Guest (Feb 15, 2011)

nate42 said:


> Great post!
> 
> Typo in your excel on cell B7, should be 1.097 not 0.970, that ruins the calculations for the 5th gear so worth mentioning (not trying to be a smart ass).
> 
> Are you sure that Quattro Sport has a different gear ratios? That wouldn't make any sense production wise. Also stated Quattro Sport gear ratios don't make much sense. 4th and 5th overall ratios are almost identical and 6th is way too short.


No probs. I want to know about any errors in my spreadsheet. Have you downloaded the latest version which I have significantly revised & reformatted to make it clearer? I did notice a significant error so maybe that was it...? Cell B7 is now the number '39'.

Your timing is unfortunate on checking this post as I've just revised it about 30 times to get the table formatting correct! Go back and have another look at it all now...

QS gear ratios are not from the workshop manual, but the sales brochure pamphlet, so I can't comment on their veracity. Only to say that they would have almost certainly revised them to take account of the quite different boost profile. I haven't analysed it to that extent though.

Thanks for looking and feedback.

Doug


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