I got O.E. manifold gaskets for my 1996 camaro z28 (part number 12552469) and I just recieved my SLP shorties today (30017) and the holes on the gaskets and the holes on the manifolds don't line up, at all. The gaskets go out farther than the headers (the holes). I know they are the right headers, do I have the wrong exhaust gasket? The 4 inner holes line up, but the outer two don't, they go out farther. HeLP

 

nope you probably have the right ones. The stock manifolds are made to use the outside hole on head while all headers use the inside hole. You might be able to modify the gasket but i would just buy some new ones rather than worry about leaks

 

So are you saying that the head has another hole which the stock manifolds do not use?? I just measured everything out, and the holes on the outside won't work from the heads to the headers (crude measuring, but as good as I can with the engine in the bay.) Its about a half inch short on each end.

 

The GM bolt pattern on the heads is
oo0o o00o o0oo
The big holes are exhaust ports and the little ones are bolt holes. Your header is missing the extra bolt hole on each side thats the way they all are. The exhaust manifolds uses this extra hole on the outside.

 

There are manifold gaskets, and header gaskets. I think Felpro 1406 is the appropriate gasket for headers.