Audi A4 AJL (180bhp) 1.8T tuning


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I'm new to the forum and pretty new to Audis too. I've had a B5 A4 Tdi before but now I have a 1999 1.8T Quattro Sport. I bought the car as I'd heard quite a lot about the engine's tuneability and I've ssen loads of magazines with 350bhp+ 1.8Ts in them.

I'm no stranger to modding and have tuned a couple of Imprezas to around the 400bhp mark.

So, I rang a well known VAG tuner last week to see what was on offer and was told there was "little or nothing they could do for the car"! I've read a lot of threads on various forums about KO4s upgrades and the like and getting low 200s out of these cars sounds easy, but I'm after around 300bhp and 300lbsft at least and there seems little or no detailed information about what's involved.

Obviously I need to cover the basics first, exhaust, intake, front mount intercooler etc but if you are looking at big turbo and injectors and remapping there seems to be not much available from the tuning websites, particularly in the UK.

Getting 280 out of a TT seems a simple matter fo a chip change so why the issues with the A4 Quattro?

Any help would be appreciated!


"Stick a V8 in it!"
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The basic issue is the turbo fitted is tiny, and bolt on upgrades arent all that great either. The longitudinal engines (A4 and passat) are less well cared for in terms of upgrades as the turbo fitment is different to that found in A3/TT/Golfs etc.

The turbo on the AJL is the same as that fitted to the AEB (150hp) engine, and is maxed out at around 190-200hp

You can buy a K04-015 for around £800, but this is still tiny compared with the TT K04, and will probably net you around 230-240hp.

Frankenturbo or a Scroll hybrid might eeke out a little more, but in reality much more than 250 on the standard frame turbo isnt easy.

I would suggest you go big turbo from the start. You have a few options for 300hp, GT2560 (aka GT28R) or the GT2860RS (aka GT28RS) are both good choices for your power goal, and the 2560 can be found on Nissan 200SX S15's making them a viable used option. New both are around £1000.

You'll then need a manifold (i'd suggest a PSI Concepts item, they're pretty tasty looking and will allow you to retain the airbox and suchlike if you choose) and pipework sorting out. PSI again do a kit with oil and coolant pipes to fit a variety of turbos, so probably a fair shout to look at that route.

FMIC and a 2.75 or 3" exhaust.

I wouldnt bother touching the inlet side. Stock airbox will flow 300hp without problems. You will need to convert the housing to fit a 3" MAF, you will need larger injectors (Vauxhall VXR items are probably a fair shout and available cheaply, or you can use SAAB reds at a push)

TQS uses the same fuel pump as an S4 as standard, so wont struggle with 300hp.

After that its just mapping, which while tricky can be done. I'd recommend MRC, although their work on another members 1.8TQS is a bit wonky. RTech also seem to have a good write up with tuning these ECU's, however they dont have a 4WD rolling road last i heard.

Its probably worth bearing in mind that these engines only real weak point is the connecting rods. For a genuine 300lbft, i'd be wanting to upgrade the rods, as thats certainly in the danger zone for the standard parts.

You may also want to look at upgrading the clutch, i'd recommend going down the 240mm route, using an ECS or TTV flywheel and an S4 clutch plate and cover.


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That's brilliant help, exactly what I wanted to know.

Many Thanks!



Registered User
This is gold dust!...i too have the AJL and have you found it more difficult finding suspension and brake parts due to it being the 180 bhp model as opposed to the 150?? But thanks again Aragorn :)

Broken Byzan

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a decent tune and a FT4t turbo should net you 250 with supporting mods. Problem is, while it's a bolt in solution, you really need a decent exhaust, fmic, injectors, etc etc.

Lee has done a budget ish build on his car, maybe that's the way to go


Having actually built a 400+hp A4 TQS, my advice would be to really think long & hard now about how you will tune the car with a larger turbo fitted, this will be the big headache part of the build. Other things to consider regards weak points are, Rods as Aragorn has said, the timing belt pulley IS the weakest point on these 1.8T's, plenty of these have let go and killed the motor. Also the timing wheel bolted to the crank has a nasty habit of detatching it self, tack weld the bolts to the wheel to stop them backing out. The sodium filled exhaust valves also have a tendency to seperate, obviously ending in tears. My build thread is in the project room if you want to have a butchers, I didn't go into the technical details to make it an easier read, if you have any questions feel free to PM me :).


Registered User
Thanks for that.

This is quite an old topic resurrected. I had actually abandoned my plans for the big turbo exactly for this reason. The ease of getting the hardware, but the nightmare when it comes to the software. JBS are doing a kit (the APR one) which is good for around the 280-300bhp mark but at over £4k it is madly expensive, but the advantage is it is basically a drive in drive out conversion, so it CAN be done!

However, since talking to R-Tech they are willing to do the mapping of a car to this spec with the hardware being sourced by me. Few tuners appear to want to do this. If you haven't bought the bits off them they don't seem to want to know.

So I'm back on it now. So, gathering together my parts as funds allow. I'm going to start a thread on the progress soon.

Good to have the offer from you IN2Deep, thanks and seems like you aren't a million miles away from me either, good to know. Cheers.


No worries dude.

Only just clocked this is an old one! I can't keep up. I rarely visit this forum these days so my apologies. £4K for a turbo kit with tuning is absolutely nuts. If your crafty its astonishing how reasonable it is to put a car together, its never cheap but it comes down to how much. My opinion is just go big, proper big or don't bother, another 50-60hp for a big outlay just ain't worth it, it really isn't that much more to go for crazy numbers once you have rods in the motor.

My advice regards mapping our TQS's is get some references and chat to those people who have had there's mapped before building it. I went straight to a standalone ECU which appears to have been a god send really. I feel for those who have built a TQS and can't get it mapped to run right, sure standalone takes alot of the finesse out of the car but my car is raw, angry and properly quick and thirsty :)

If you ever need a hand or some advice just shout, I'am only 30 minutes from Manchester, in the B5 anyway!