Bad manifold gaskets

[dmaxweb]

Originally Posted by alexiskai

I'm confused. The manifold is cast iron, so the linear thermal expansion coefficient is 5.8. The rings are mild steel, so the coefficient is ~6.5-7.0. That's close enough that the expansion you'd get at normal exhaust temperatures is like going from a slip fit to an interference fit. Unless you're needing to drive your homemade rings in with a hammer, it doesn't seem like you'd need to worry about buckling due to expansion.

What about rings cut from 316SS tube (1.500" OD X 16GA (0.065"))? With a significantly higher coefficient than cast iron can they still be solid or is a gap needed for thermal expansion?