Con Rod Question

[BigMuz]

imho rpm is harder on rods than boost.

Having said that, I know a bloke on here whose dad switched the pulleys on his udnerdriven 202 with a 6/71, and he drove downt he road and it went soft, pulled it apart and the rods had banana'ed into an s shape. That was pretty extreme though, maybe 40 pounds of boost on stock 6 cylinder holden rods :D

[260BC]

As an example, turbo RB30 motors risk bending the conrods ~500hp (give or take a 100 or so). Nothing to do with rpm, preignition or anything like that, the reason is fairly obvious no?

[Turbo 351]

As an example, turbo RB30 motors risk bending the conrods ~500hp (give or take a 100 or so). Nothing to do with rpm, preignition or anything like that, the reason is fairly obvious no?

Yes, they still have a limit, but would one let go at say 300 HP with either higher revs or detonation, or a combination of both (lets assume the pistons have held together).

[C0V3R]

Only 40psi. Soft*.





*Soft as something hard.

[The Pupat]

Yes, they still have a limit, but would one let go at say 300 HP with either higher revs or detonation, or a combination of both (lets assume the pistons have held together).

depends how many revs are needed to get 300hp.

Looks to me like corky bell is mostly correct but is making a lot of assumptions to dumb it down.

turbo load is less on con-rods is less than RPM ... with in reason, would be a better statement. Con rods by design would be stronger in compression than in tension so they would also be more likely to fail based on RPM than load.

[Billzilla]

FWIW, rods themselves rarely fail - rod bolt failure, however, is a far more common thing.

[BigMuz]

Yep Bill, and rod bolts do nothing on the power stroke. So thqat is why I tend to think that rpm is tougher than boost or cylinder pressure.

Detonation is tougher than either though :D