looking at various intake manifolds for nailheads and they differ in width can anyone tell me when they changed and what goes with what. I have a number of manifolds to ID thanks
The really good nailhead experts are at http://groups.yahoo.com/group/BuickNailHead They can identify what you've got by casting number. The engine specs at nhra.com also have casting numbers. I think the difference is when displacements increased to the 401/425, the bolt hole spacing from side to side increased by 1/4 inch.
Here is a link Try this link: http://www.buicks.net/shop/reference/nailhead_casting_numbers.html John
Check out this thread for pictures of the 2 side by side. http://www.v8buick.com/showthread.php?s=&threadid=3759 Bill