RallyBoy

iTrader: (1)

Has anyone used this method of tightening head bolts?
This excerpt is from arp's website.

1. The friction factor changes from one application to the next. That is, the friction is at its highest value when the fastener is first tightened. Each additional time the fastener is torqued and loosened, this value gets smaller. Eventually the friction levels out and becomes constant for all following repetitions. Therefore, new fasteners should be tightened and loosened through several cycles before applying final torque. The number of times depends on the lubricant. For all situations where ARP lubricants are used, five cycles are required before final torquing.

dhdenney

iTrader: (53)

Yeah just set your torque wrench in incremental values and work your way to the final spec.

RallyBoy

iTrader: (1)

so tighten all the bolts in incremental values to the final spec and then loosen all of the bolts and do the same thing again four more times? this is the way i understand what arp has written.

dhdenney

iTrader: (53)

I hadn't read that before but it does read that way. If ARP says it, then I'm sure it's a safe method.