twistedbowtie

on my 1995 z28 auto. i have pacesetter long tubes, pacesetter off road Y, and a slp loudmouth1 catback. i stay down a gravel drive. when i drive down bump roads slow on my drive way i hear what sounds tobe the headers knowing on something. its under the front floorboard. ive recently replaced turque arm/trans cross member bushings. although it dont sound like ether of them would. its alott lower. anyone ever have this problem or ideas what it could be?

thanks, Dustyn

Feenix

Yeah I did, same situation too, any time I was at my grandparents place where they have a gravel driveway I'd feel/hear my y pipe thumping on my floorboard. My motor mounts were a little weak, some prothanes solved the issue.

twistedbowtie

alright man thanks for the help
Dustyn

94Zee28

could also be hitting the k member. I believe mine did on the passenger side right behind where the lower A arm mounted.

bobdec

My pacesetters, hit the driver side floorboard raised section just in front of where the fuel lines run. The pipes have an indentation to clear this but they still hit under acceleration and bumps. I think the correct thing would be to setup the headers for clearance when the manifold bolts are still loose. You may be able to get 1/2 inch play at the collector end just by the slack in the bolt holes w/o having to oval out the holes. I used a hammer to get more floorboard clearance, not the best solution. Problem is raising the engine higher could make it worse, lowering the transmission crossmember 3/8 inch using shims (4 washers) will lower the rear of the engine, and point the collectors lower, but you have to keep driveshaft alignment in mind if you go that way.

nintythreeZ28

my pasecetters... the only way i can describe it is that when i get on it, it feels as if i just hit a racoon and his face slammed the floorboard right under the pedals.

this is what im working with. i still havent found it...

LT1553

I have the exact same problem with my new pacesetter LT's and off road y. If i accelarate hard the driver side collector nails the floorboard and really sounds and feels terrible. I guess I just need to make more space at the floorboard. I did use a hammer to clearance the collector but no luck still hits.. Guess i didnt clearance enough. I wonder if there is a spongy like soft material that you could wedge in place between the collectors and the floorboard to keep that noise away? Guess it would have to be something that is heat resistant..

nintythreeZ28

ya. header wrap whatever it is and it MIGHT not catch fire.

vangill

bfh mod

ascastil

On my old setup with the ory, the exhaust shop welded a rod near the fuel lines on the ypipe for clearance of the fuel lines. It was welded on the top of the pipe in direct contact with the floor board. On that rod I slit a piece of hose lengthwise and slid it onto the rod, it dampened any bumps and vibrations and gave a little clearance from fuel lines. To get a better picture in your head, the best way to think of the shape of that rod is like a soccer goal post, two 90* bends with a hose on top. That hose is wedged in between floorboard and the rod that was welded on pipe right after the collector. I had to use a prybar to slide the hose on.