leak
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The gasket may not be damaged; but the flanges may be heat-warped to the point that there is leakage around the gasket in some areas.
With welded headers, the only way to know this is to remove all the attaching bolts and see how much variation there is in header flange clearance to each outlet pad on the cylinder head.
This is a common problem with headers, as they are not usually heat-tempered to remove welding stresses and THEN machined flat. So, when new headers are installed and run, the exhaust heat causes those welding stresses to release and the headers to WANT to warp, putting everything in a bind.
You might be able to just re-torque the bolts in the area of the leakage to see if that reduces the problem.
You might find some thicker header gaskets that may be able to absorb the amount of warping in your headers. Installing them would be a lot easier than removing the headers to have them machined flat.
With welded headers, the only way to know this is to remove all the attaching bolts and see how much variation there is in header flange clearance to each outlet pad on the cylinder head.
This is a common problem with headers, as they are not usually heat-tempered to remove welding stresses and THEN machined flat. So, when new headers are installed and run, the exhaust heat causes those welding stresses to release and the headers to WANT to warp, putting everything in a bind.
You might be able to just re-torque the bolts in the area of the leakage to see if that reduces the problem.
You might find some thicker header gaskets that may be able to absorb the amount of warping in your headers. Installing them would be a lot easier than removing the headers to have them machined flat.
