Posted by Tom Petroff (IL) [172.68.37.51] on Sunday, January 31, 2021 at 11:58:05 :
In Reply to: Broken manifold, Follow up posted by Greg Coffin [162.158.75.137] on Sunday, January 31, 2021 at 11:29:38 :
The front is where it cracks most of the time.
Some would say probably 50/50 between front and rear like yours.
Turbo might have helped it, but cause is heating and cooling cycles in the long runner.
Known problem.
That's why they went to two and three piece sliding manifolds on the later inline engines gas/diesel to alleviate the problem.
My m37 was cracked on the front runner when I got it.
Replaced it with NOS so far so good.
I think John @Midwest or Brett Mulins still have some NOS or reconditions.
Tom