jktcummins
24v GOD!!!! HAHAHA
- Joined
- Apr 1, 2007
- Messages
- 2,450
my ARP's are at 140lbs and holding just fine.
I've got mine set at 125 and I re torqued them 5 times.
They've held for almost 2 years at 75psi and 4000rpms.
Cliff, I think that something isn't flat there buddy. Should have held unless your drive pressure is wicked high. I have seen a gasket with studs blow at only 50psi of manifold pressure. He was making over 90psi of drive pressure though with his homebuilt twins......not cool.
I really wouldn't recommend torquing them more than the ARP specs. I have a feeling that they know a hell of a lot more about fasteners than any of us do.
Gus is right, make damn sure that all the surfaces are clean. Really clean.
Good luck!
Please explain to me how 90psi will blow a head gasket.
So lets say 90 psi drive pressure--then there's 90 psi in the cylinder during the exhaust stroke. There is no compression of this 90psi air, like during the compression stroke. All it is, is 90psi. That's it. When the Exhaust valve closes there is still 90psi in the cylinder, but only for that brief moment at and after TDC (assuming overlap). The piston then starts the downward stroke, increasing cylinder volume and taking in charge air at manifold air pressure. The charged intake air is the only volume ever compressed, and at 16:1 or whatever comression ratio, combined with the forces exerted during the combustion event, is a heck of a lot more stress on the gasket than 90 psi.
I'm not trying to downplay anybody's intelligence or their understanding of how an engine works. It just doesn't make sense to me when people bring up the "excess drive pressure blows headgaskets" adage.
Id say overtorqued.
NOT OVER TORQUED
well done at 140. Id just say you've streched em one to many times. prolly worth it for a new set.