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We have two of them in our garage. This is the engine bay of a 1970 Chrysler New Yorker 4 D sedan


Iseriously doubpt that the reason for the breakage is the pistons or rods themselves. Shouldn't be at that power level. We have a 440 with a 6-71 that makes about the same power and it has been together for almost 30 years, but will be gone through this winter. We also broke a 400 with H-profile rods and a supercharger last summer, a rod broke. But that was because a cylinder wall cracked, water got on the piston and since it doesn't compress too well something has to give up... Although propably not the reason in this case, I would check the cylinder walls of that cylinder carefully just to be sure. Detonation might be one reason, but I would assume you should rather see it as gap walk first. And of course the pistons you have are tanks, but unless you wind it very high, I think it shouldn't be a major problem.



Yeah I'm thinking he may have spun the engine too high coupled with too much timing.
I see folks with prochargers that have basically stock bottom ends pushing more boost than that and living.