exhaust hitting

**JunkyardZ** · 06-13-2010, 02:02 PM

When I first did the exhaust I had no issues with it hitting but now it does and the car feels very sluggish off the line at WOT and has a lot of noise associated with the y pipe hitting. I had a theory that this was messing with the knock sensors which would screw with timing and could kill my power but I hooked up a scan tool and went for some hard launches and never saw any activity from the knock sensors. Maybe the scanner was too slow to catch it though? Thinking about just having a custom y pipe made but does anyone else think my theory could be true or is it all just in my head?

**pajeff02** · 06-13-2010, 02:53 PM

Why not just get under the car and adjust the exhaust so that it does not hit? Chances are something loosened up or moved due to road surface contact. Only other option is that the motor mounts are failing and this is allowing more movement -- hence the exhaust banging.

**JunkyardZ** · 06-13-2010, 03:31 PM

I think what happened is I tried to get the y pipe not to hang so low and maybe that is why it is hitting now. This particular y seems to hang kinda low on the drivers side. I would like to stay away from the stiff motor mounts if possible. Also, its not really the noise that bothers me, I was wondering if that it was somehow hurting performance.

**sjsingle1** · 06-15-2010, 02:10 PM

poly.MM........its a permanent solution

**xmarkx** · 06-16-2010, 01:56 PM

alot of people have said that after replacing their motor and tranny mounts with poly that the long tubes and Y fit better under the car

**Cutlass** · 06-16-2010, 06:46 PM

Originally Posted by JunkyardZ

but I hooked up a scan tool and went for some hard launches and never saw any activity from the knock sensors. Maybe the scanner was too slow to catch it though?

yep most likely. a lot of aftermarket scanners are slow

**Mesterious** · 06-16-2010, 07:58 PM

Originally Posted by sjsingle1

poly.MM........its a permanent solution

+1

I installed LT Headers and ORY one weekend when I had time but I didn't have time to do Poly MM but I did have them. Well I heard a good bit of tap tap in P and N Some in D too. Well I got my mechanic to put them in for a relatively good price cause I deffinatly didn't want to take the exhaust off again.... Well Now 99 percent of the tapping is gone and my car feels alot more solid. My stock rubber driver side motor mount was busted and my car had 50K miles on it.