I have a 2001.5 S4 with a GIAC Chip. When I punch the throttle it will hit a spike in boost to around 20-22lbs and then go back to 15ish lbs.... then slowly work its way back up as the rpm's get higher.

Is this normal?

 

yeah, it will spike seems kind of high, what do you mean goes back up when rpms get higher, do you mean it goes up to 22 psi again. mine spikes up to 18 psi and stays at 15 psi for my full boost, maybe you have a race n75 that holds your boost higher. with out really seeing it hard to say.

 

Yeah, it will spike to anywhere between 20-22 depending on when I punch the throttle. Then the gauge will immediately go to about 15 and as I wind out the gear it slowly reach about 18. Sometimes its hard to watch because I'm trying not to take my attention off the road... I'll have to get someone to look at it in the passenger seat.

 

22lbs seams high. I have a peak hold on mine and the highest it has hit was 19.58lbs. the KO3 are small turbos so they will get up fast and then fall on there a$$. danty little things.

 

yeah i say check your dv's maybe there are on upsidedown, it happens alot for some reason or they have failed and are not dumping so you hold more boost.

 

Ok but in other words... its normal for the boost to peak like it is and then hit a lower number. I just wanted to make sure it wasn't a boost leak. Thanks everyone.

 

yeah that is normal with any car they will build pressure till the car tell them to dump your is jsut kind of high at first but other then that normal, you can jsut check for boost leaks but with a bipipe i wold say no with that hight of boost.