Took my apr stage 3 B5 A4 quattro to the dyno, I was dissapointed with the best pull at 198whp. I thought with the stage 3, test pipe, carbonio intake, apr fmic, and electric fan that it should have more power, the previous owner also gave me an old dyno sheet that showed the car around 250whp. Since the shop was not an apr dealer they were not able to log the car, but they did tell me that the af ratio was all over the place, sometimes running too lean but not dangerously. Boost is good, there are no codes and car seems to be running great. Sorry that I dont have a print out or any other info from the dyno, but Im going to go to an apr dealer for more dyno runs and a log, but I want to do a few things first before spending money on the dyno again. The previous owner put in a rebuilt motor about 5k miles ago, but alot of the old sensors were probably reused. I was thinking of replacing the MAP and front o2sensor, MAF and rear o2 sensor was already replaced. Anything else I can replace that might help?

 

What injectors are you running? Also, are you on a stock/original fuel pump? An upgraded pump may help you take advantage of big injectors, and if your pump is old it may be getting tired (especially with the higher demands of the bigger boost), which would explain your erratic A/F ratios. See if you can have them log your ignition timing to see if it's being pulled back and killing your power - that'd be a clear indication that pat of your setup is not carrying its weight. Also, installing am EGT gauge and sensor, and understanding what the temps indicate, can give you a real-time look at what's going on in your engine. Check/change your plugs too and be sure they're gapped correctly.

I'm assuming you've checked for boost leaks and that your gauge is showing the expected boost pressures across the RPM band.

 

Injectors are whatever come with the apr stage3 kit, not sure about the pump since everything was done by the previous owner, from reading around it seems the stock pump should be fine so I didn't think of it, but good call on it getting tired, ill proably replace it with the bosch from 034 motorsports. Boost is good and plugs are new but the shop put them in not sure if they gaped them.