Renegade403

what psi should k04 turbos be running at on an '01 s4? I'm looking at an s4 with k04 turbos,unitronic tune at 12.5 psi. I was told that this is not right at all so it needs some serious work. I'm just checking to see if what i was told is actually correct?

1sadavant

The psi is what ever the tune calls for...if the tune requested 12.5 psi then that is what you are going to see (highly unlikely that someone would tune for that) If the turbos are running off of oem k03 software it should hold around 8psi. Stage 3- giac around 16 psi, full blown stage 3 varies, but most spike at 23-24 and hold at 21-22. I would pressure test the car first.

Renegade403

Why is it unlikely that someone would tune for that? (sorry I'm new to audi and turbos). Also what is required in order to pressure test it?

1sadavant

It is unlikely because this isn't a great deal of boost to challenge these turbos. As I said before K04's can push a lot more pressure than 12.5. Limp mode is 5psi. I believe a stock B5 RS4 is 14 psi on K04's. (only found for sale outside of USA, few exceptions exist.)

If someone is going to spend the money on a tune, they most likely will be asking for more than 12.5 psi. This is probably slower than most stage 2 k03'd cars. There is something wrong with the car! Unless this person asked for the most reliable tune out there (i.e. longest lasting life on turbos), sacrificing the potential power available. Again, this just doesn't make sense.

Who did the tune? Where is the car located? Any additional info would be appreciated in helping you decide.

Pressure Test: http://www.awe-tuning.com/media/pdf/...ure_tester.pdf

Justin:NorCal

According to compressor maps 22psi spike holding 20psi is the way to go. Anything above that is out of the efficiency range.

thejulex

Is it manual or tip? Tip might not handle more TQ without tranny/TC upgrade.