Ok guys got a 87 gn 36 lbs injectors atr chip and good exhaust good fuel pump and the car runs like great idles and all but heres the weird part.When power braking the car up to get the turbo off its butt and spinning say 3 to 5 lbs or higher then quickly letting off accelerator pedal you can hear a gurgling coming from the air intake and its got a k+n filter and when you have the hood open and doing this you can actually watch the intake tube from the turbo to mass air sensor to the filter shake kinda whats up with this.Is it the turbo or is this normal or what the car really works good and iam impressed with it just started doing this like couple weeks ago well thanks for all of your help mike
This is normal, it's called compressor slam. When you close the throttle quickly the air you've compressed into the IC has nowhere to go, so it backs up through the turbo which is still spinning and trying to compress even more air. This rapidy decelerates the turbo, and when the air *slams* past the compressor it makes that "chuff-chuff-chuff" sound. While it *is* normal, it's not the best thing to do to your turbo as it puts stress on the bearings and seal. I try not to just lift off the gas under boost if I can help it, but rather lift slowly. The K&N filter makes it sound louder, but it was there even with the stock air filter, you probably just didn't hear it.
Fast Freddie