The cracks would be along the welds and tend to propagate forward to aft. Even if there are no very evident cracks it is easy to strenghten the welds with the engine out but very difficult to do with it in place........Bob
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Bob Beck
39 Chev PU
69 big block Corvette
55 Buick 66C
57 Buick 46C
55 Olds S-88
56 Chrysler St. Regis
AACA, BCA, WPC, USHGA