Exhaust questions


So putting on a SST 3" dp and cat back. Question is should I or should I not use a test pipe? If I don't use a test pipe because of the boost spike issue I have read about is true, does anyone sell a 3" in/out cat direct fit?
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The only 2 companies i was ever aware of that sold the exhaust for these were ATR and RPM/ Race Proven Motors in Chatsworth Cali. I know that ATR is long gone, I'm not sure about RPM though.
I've used a test pipe for 15 years with no problems. A test pipe can be used from just about anywhere, there's not much special about them.

As for exhaust, RJC Racing, Hooker, and Flowmaster still make kits for these cars, but I'm still rocking the ATR single shot I got in 2003, can't believe it is still alive and well. I guess that speaks to ATR's quality or how long my car has been broken!

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I'm going to use a sport machines dp and test, and a rpm cat back.....so your saying with the test and cat back you haven't had a spike issue on your GMC (not Buick)? Are you running an aftermarket dp?
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Just to be clear here, I'm speaking in reference to using a test pipe on a GMC Typhoon, and not a Turbo Buick. I'm trying to gage others experiences with using a test pipe and having or not having a boost spike with a stock turbo. This is due to removing exhaust back pressure from the system and the WG actuator + WG passages not being able to react fast enough. And yes I have also tried to join SYTY.NET.