Looking for help getting more low down torque on S4 B5

[Mikesone]

Hi
Looking to see if I can get any advise on improving low down torque on an S4 B5.

There is pretty much nothing from the engine until I hit around 2500rpm, then it picks up well.

Not really sure where to start, so looking for ideas I can follow up on and try out.

The car is a homebrew done on the cheap, has K04's, 5Bar Apr, 550CC injectors, HP fuel pump, boosting at 25psi, but less than 0psi till around the 2500rpm.

Does have a stage 3 ECU I believe (but not sure) and a larger 85mm MAF with race N75.

Exhaust is 3inch decatted downpipes with 3inch straight through pipe to aftermarket muffler.

Things I want/still need to do (engine wise) is the ICM delete and uprated intercoolers.
(Not sure is these would help much, get a few missfires but always low single digits, and still no power even when cold, so no intercooler heat soak.)

Don't get me wrong the car flys, but just nothing down low.

Any suggestions I can try out gratefully received.

Thanks

[Schtug]

TDI swap?

[FlyboyS4]

I would start by looking at the logs for the wgdc, requested and actual boost.

Next checking the wastegates to see the preload is correct and they are functioning properly.

0 psi from K04's at 2500 rpm is abnormal.

[Mikesone]

Thanks Flyboy,
Appreciate the advice.
Haven't really used the vagcom other than reading and clearing codes when troubleshooting, so should be fun figuring out how to use the logs.

And of that fails, I guess I could go with a TDI fitted in the trunk.

[Schtug]

I guess I could go with a TDI fitted in the trunk.

That's the spirit! Lol

Jokes aside, it's definitely abnormal for it to not build any boost below 2500 rpm. My stage 3 car is quite happy to make boost below 2k rpm. Check measuring block 115 on your vagcom while driving around and see what requested boost is in your dead zone below 2500 rpm. Your problem may just be tune related if the car has always been this way.