/4 shortblock assembly + HP limits, case, crank and rods....how much abuse?? Options

[Mueller]

Let's say we take the stock heads and cylinders out of the picture and use heads/cylinders that are overkill and robust....

what is the next weak link in the motor?

are the rods going to fail once we start hitting the 200+hp mark?

will the stock crank turn to putty at 7000rpm?

what about the case??


at what HP range before it cannot hold everything together and gives up scatering it's internals all over???

[john rogers]

I tried running the 200 HP stroker four for several years and finally broke a Pauter forged rod. Problem was the long stroke of the crank coupled with short rods put too much stress on even really great rods and one failed on the front straight of the CA Speedway. I'd say use stock stroke with a forged crank and rods and go with larger bore and very very good heads that flow well and you'll get an engine that will last a little longer. I'd also recommend a dry sump system, not for the cooling but the huge increase of oil supply you'll get at 6000RPM or more should lengthen the engine life. Use at least a two stage pump and three stage is even better. But I gave up and put in a six and life is much better now!!!