Originally Posted By sr4440
Originally Posted By MR_P_BODY
Originally Posted By sr4440
I would be interested in knowing what the max timing was on the blocks that cracked. the reason i ask is i run 843HP (corrected) on my 400 (aluminum caps and griddle) and we put a blower on one and made 1240 hp but kept cracking upper cylinder walls (that block was cross bolted and had a griddle on it also) I run 31 degrees of timing.



Joe


They are cracking for one reason... detonation... to SR4440
31* is a lot on a blower... but other factors also come into
play... fuel, wall thickness.. and cam.. and more... to the
OP... did you put the alum caps on at day 1 of that build and
what was the timing, fuel and cranking pressure
wave


I am sorry, 31 was on my NA junk. I think we were around 21-22 with 10 PSI of boost on the blower.

Joe


Years ago I ran a 383 block but with a destroked engine
that turned some high rpm...everything was light and
it was a tunnel ram.. I measured EGT on all cyls just
to see if the flow balance was decent... that engine
lasted till I sold the car and it was still running..
of course this was before the 400 blocks
wave