Originally Posted by tclederman
The bottom manifold in the "Compare" photo has a location and boss for the vacuum-wiper fitting that is different from any I have seen up through 1961 (I have not seen later 235/261 intake manifolds).

I have a late (58-62) Canadian Pontiac 261 that has an intake similar to that one. The 1956 261 I have has the older style.



1952 1300 Canadian 1/2 ton restomod
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