Exhaust Crossover Comparison

Exhaust Crossover Port Matchings
With Head	And Manifold	Use Gasket
1965-71	1965-71	1965-71
1965-71	1972-79	1972-79
1972-79	1972-79	1972-79
1972-79	1965-71	1965-71**

** Use thin sheet stainless steel as a block off plate.

Beacuse the hole in the early intake (and gasket) is larger than the hole in 72 and newer heads,
the exhaust is able to jump over the gasket and into the dead hole above the crossover.

Either fill in the 'blind hole' above the exhaust crossover on the 72 - newer head or use a stainless steel block off plate.
Using the plate will make the crossover not able to heat the under side of the intake manifold. Cold drivability may be affected.

Either fill in the 'blind hole' above the exhaust crossover on the 72 - newer head


or use a stainless steel block off plate.

Using the plate will make the crossover not able to heat the under side of the intake manifold. Cold drivability may be affected.

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