# apx engine 400+ bhp what tuning mods are necessary



## max2013 (Apr 6, 2019)

Hi Need your heads, im looking at buying a TT with a APX engine, child hood itch that i need to get rid of. Ive seen many tuning guide's online but non that show what is required for 450bhp+ mark.

What is required for 450bhp+ with high torque levels?

Thanks again


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## StuartDB (Feb 10, 2018)

10 to 12 thousand pound 

have a look at desertstorm's (karls) thread he recently has gone big turbo so you can get some ideas I think the latest fashion are G25 / G35 turbo's

or head over to ASN there are several big turbo builds there.


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## max2013 (Apr 6, 2019)

thanks for the quick reply....bloody hell really? i was reading that the engine was already forged to some aspect.

Not easy to tune above 280ish


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## StuartDB (Feb 10, 2018)

350(ish) is doable with

air intake
fmic and pipe work
3inch downpipe sports/de cat and cat back exhaust
fuelpump
injectors
forged rods
supertech inconel valves
hybrid turbo
high flow manifold

but it's all the extras you will need say "forged rods" and "exhaust valves" <- that is near 1K in parts - but you will have to also change the bearings and rings, will the bore need a hone? have the head checked and skimmed, you get what I mean, and you will find other bits are broken whilst taking it apart.

also an APX is narrowband so has no EGT sensor which is a key to mapping the engine as it offers protection.


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## infidel.uk (Feb 21, 2015)

apx engine myself and it cost me close to 3k just to make 300 , think about it , because you can have a lot of fun with that money lol

i had to buy

hybrid turbo
front mounted I/C
injectors
fuel pump
tip
air filter
plus mapping
plus having the turbo fitted.


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## rakrynaz (Mar 30, 2019)

Sorry to hijack the thread, but I'm guessing these mods also apply to the BAM engine when pushing it? You guys mentioned hybrid turbo; what's the best turbo that can be bought with the max power gain?

I'm looking to push my car the same as OP to the absolute limit in the next 12 months, so regardless of cost, please feel free to throw names of turbos out there and any requirements necessary prior to installation  Thanks.


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## A_Banging_Donk (Apr 22, 2017)

APX 280, you'll need tip, full 3" exhaust, FMIC, injectors and preferably wideband conversion. Stock turbo & actuator is pretty much maxed, you'll need to go big turbo for these numbers. Like others have said, do rods & valves while the head is off.. exhaust manifold goes without saying. You're looking at a big bill when all is said and done.


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## StuartDB (Feb 10, 2018)

Hey max, regarding your statement mentioning 'forged internals' in the Audi 1.8t the crank in our 225 versions is forged but the rods bend or break at 300 (or less) ft_lb torque. 
To be fair I have loved putting forged rods in as i have had no end or unexpected map 'steps' 'jolts' 'jumps" 'surges' and have some level of confidence.

But you probably need to think hey..
I want max from stock internals (stage 2 ~270ish)
I want max from a k04 framed turbo ( hybrid -350~380(ish))
I want max from a big turbo stroker (400-627.5)


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## infidel.uk (Feb 21, 2015)

wak is running around 350 with stock rods.


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## rakrynaz (Mar 30, 2019)

StuartDB said:


> a big turbo stroker (400-627.5)


With power like that and a name to match, I hope it comes with a free roll of tissue!

On a serious note; is it actually possible to get around 600bhp from a TT Mk1 without blowing up the car? Just so I know what I'm aiming for before I start becoming wrinkly 8)


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## StuartDB (Feb 10, 2018)

Wow.. but, that's a terrible example. 350bhp or 350foot/lb torque. 350bhp is what... 280g/s maf it takes a second to estimate from a log.

I would love to see the logs, to view the torque onset.. I spent about 30 hours trying to get boost open loop working with my 'hybrid' chra and couldn't get over [email protected] 22.5psi from about 2800rpm (according to log data). It simply ran out of steam. But I have a rebuilt chra back from turbo rebuilds and will try a ported OEM hotside rather than that Chinese hotside I had bought (I think the waste gate pin is warped) and a new dw65v fuel pump as highlighted in my thread even with the stock turbo I'm hitting 19ms in a 20ms duty cycle, which is maxed out 550 injectors with a 3bar fpr, although I am setting desired AFR to 0.82 on WOT so maybe a little too rich.

What really annoyed me is when I was trying to set up pre-control PID, everyone else's example base data was all 300+g/s because they were running s4s with k04 turbos.

http://nefariousmotorsports.com/forum/i ... ic=12352.0

The fact the OP said they were looking for 450bhp makes the rods a moot point anyway, no-one wants to be scared of putting their foot down do they? I still am scared of leaving my foot on the clutch pedal as I dont know if it has been replaced/repaired already.

I did see someone saying TT shop has suggested stock 1.8t can handle over 300lbft torque too, which seems crazy being they only sell revo generic maps and the revo stage 3 recommends replacing the rods.

https://www.onlyrevo.com/product-detail ... 91/stage-3


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## StuartDB (Feb 10, 2018)

rakrynaz said:


> StuartDB said:
> 
> 
> > a big turbo stroker (400-627.5)
> ...


I don't go onto Audi sport net anymore, but there are several big turbo builds exceeding 600bhp with gt35 [email protected]#%

Desertstorm (karl) recently fitted a g25 which is about 450bhp if I remember rightly. But I think you get some more power from a rebore and a 2.0 tfsi crank to make the 1.8l into a 1.95l and some different cams.


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## rakrynaz (Mar 30, 2019)

StuartDB said:


> rakrynaz said:
> 
> 
> > StuartDB said:
> ...


Wow that's.....Insane.

Trying to control the car with that much power must be an absolute nightmare mixed with the craziest adrenaline rush.

That's definitely something to aim for, but I can imagine it comes at a huge cost financially.


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## desertstorm (Apr 25, 2017)

The cost of a big turbo build can get silly especially if you can't do the work yourself and have to get somebody else to do it.
Even when you do it yourself it isn't cheap, a lot depends on what you want and how reliable you want it to be. I wanted 450bhp plus that would be reliable on a track hooning around flat out for 20 minutes at a time. 
You could buy an Ebay GTXX turbo and with some Max speeding rods , big injectors a manifold from Bulgaria/ Lithuania and a custom exhaust / downpipe , A Bosch 044 copy pump , welly cooler and an uprated clutch you could get 450 bhp for somewhere between 2.5 and 3K with the mapping and other bits. But I don't know how long it would last on a track and driveability / response will be nothing like a G25 setup with a standalone ECU. 
Have a look at Badger 5's website he sells pretty much all the bits you need. https://badger5.co.uk/ 
Garrett G25-660 £1450 , Nortech V-Band manifold £950 , Downpipe £470 , injectors £250, wastegate £350, Rosten uprated springs £230, Supertech exhaust valves £250, Ignitron stand alone ECU £900, Sachs 4 Puck clutch £250, DMF and pressure plate I got cheap £150, oil and water lines with fittings £90, Wossner forged pistons £550, Rebore block and cylinder head clean up fitting new exhaust valve guides £150. DW65 in tank pump £220. Intergrated engineering rods £500 , Gaskets new cam belt ,water pump, head bolts, main bolts and lots of other odds and sods probably £350.
That's about 7k but hopefully it will all work really well and be reliable. Just running 1.1 bar of boost and 6K RPM limit whilst running in it's quicker than it was with stage 2 mods at 275bhp and 300Lb/ft.

https://www.audi-sport.net/xf/threads/g ... st-3398770

https://www.audi-sport.net/xf/threads/g ... st-3343277


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