Originally Posted by p-streets
I have a catless xpipe and I to feel it I have a buddy with same set up says he has that also i noticed about a day or two after install so I just figured it was normal he had it also he has diffrent xpipe and exhaust also not same exact set up as me
That's good to know. I had a good friend of mine come over tonight and we put the car on ramps and listened under the car. There was definitely no leak coming from the connections between the headers and the test pipes. There was no leak from the clamps either, however, we noticed a small leak coming from the new resonators I put on in the location where the secondary cats were. We used some 2000 degree exhaust putty on the location we felt it coming from and will let the car sit overnight for it to cure.
We also noticed one of the 02 sensors looked like it was touching the heatshield, possibly increased when the car is under load, so we bent in the section of the heatshield to make sure it cleared the area. After further driving, I think it's safe to say it's just the "extra" air blowing into the pipes and the overall harmonics just being louder in the footwell area from the restrictions being gone. My friend said he is certain that's just from the nature of the test pipes (he's an engineering/mechanical engineering student) and that's just how it is. He said it sounded awesome, too
2008 (07/08) E92 M3 BPM Stage II Tuned by Mike Benvo, 6MT, Turner Test Pipes, Magnaflow Custom Catback Exhaust (Magnaflow X Pipe, secondary cat delete, Aero Resonators and Helmholtz Chambers),Vorsteiner CF Lip, Hamann Style CF rear diffuser, CF Rear Decklid Spoiler, BMW Performance Kidney Grills, CF Side Grills, OEM GTS Wheels, K&N Drop-In Filter, GP Thunder 8k Angel Eyes, Painted Reflectors.