Hey guys, I have got a problem with my LTs knocking. the knock is coming from around the area where the header and ypipe join drivers side. the drivers side is hitting the frame right where the stock fuel lines cross to the outside of the car. These headers are coated pacesetter.

Im thinking on two different ideas to stop the knock.

1. try to bend the frame and header to where they dont touch. (the header is already flattened some so it would be more bending the frame)

2. Put a steel spacer where the transmission crossmember bolts to the car. so that the engine tilts back about 1/4 inch. giving the header and ypipe joint more space.
My question about this is will it make the alignment of the drive shaft too straight causing problems.

I pointed out the area where the knock is occuring. follow the link.
http://www.fquick.com/garages/viewga...wimg&id=256395

thanks
josh

 

I had the same problem, part of it was the y-pipe was not forward enough and the flat spot was not perfectly aligned with the frame support protrusion. Fixed that but the y was still only about 1/8 inch from the frame .. I hated to do it but used a hammer and flattened the support piece, it was soft metal and gave in easily giving me an extra 1/8 inch.. Seems your engine height or angle is off a little. They don't give much room for errors with that y-pipe. I don't see altering the engine angle 1-2 degrees causing a major problem with the drive train, lowering the rear would make it closer to normal assuming the header alignment is not defective There are much more knowledgeable people out here than me. Maybe a post in the drivetrain section..

 

That is the problem. So today I flattened the ypipe some. That gave me a little room but still a little tapping. So I added a peice of steel under the tranny cross member and it gave me enough room so that the exhaust doesn't knock.

IM gonna post in the drivetrain section too and see what they say.

thanks