Originally Posted by HotRodDave
Aluminum head, iron manifold expand and contract at different rates and highly stresses the tiny bolts and most of the time it is the end bolts that break because that is where the most difference in expansion and contraction is experienced by the head and manifold.


Yep, the manifold is expanding in length when hot, contracting as it cools. That wiggles the bolt back and forth breaking them.

Funny thing is, Chrysler knew the solution, look at any flat head six, or slant six and you will see that was done to keep those long exhaust manifold from cracking or breaking studs.

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