Do they both use the same torque spec ? Because if the arp uses higher (which i have heard) wouldnt that change the clearences for the main bearings ?

 

The ARPs should use a higher torque spec. I've been told numerous times by different machinists and engine builders that if you use bolts with a different torque spec on the mains, you should have the mains honed with the new studs/bolts and torqued to spec.

I haven't seen any failures of main bolts on H22s. Unless you're running a really outrageous setup, I don't see a benefit to the main studs. On both of the track engines (H22s) we're building right now, both use the stock main bolts.