Torque specs on the mains?

[TurboDave]

I know the spec for stock mains and bolts is 100. But I'm using ARP studs and stock mains, and have lost the spec sheet. What should I be shooting for??

 

[ek02]

95 Ft Lbs with ARP moly lube, 130 Ft Lbs with motor oil is the old ARP instructions. I just got a new set of ARP main studs and it says 110 Ft Lbs using the Ultra Torque lube they came with. It says to use the torque spec and lubricant that was used when the block was line honed. Why they changed the lube, I don't know.

 

[Jerryl]

. . . . . It says to use the torque spec and lubricant that was used when the block was line honed. . . .

This is the key.

 

[S10xGN]

Dave, I went to 110# (like ek said) with the new ARP lube on my studs last year...

 

[m233roller]

Dave anything from 100 to 110 or in between those numbers with thier lube will be just fine. I do 105.

 

[TurboDave]

Thanks guys.

 

[LOT]

Thanks guys.

Can I jump in? 90 with ARP lube is more than sufficient, assuming it has not been worked on recently with different specs. Years ago I spun one of the 2 center cam bearings upon rebuild startup. Talked to Jim Ruggles about the problem. He explained that over torquing the main and over torquing the head studs, as we all do, distorts the 2 center cam bearing bores by pulling on them in 3 different directions. The 2 end bores have sufficient mass of material around them to stay ROUND, #1 and # 2 NOT. Also doesn't using ARP lube alow you to use 70 percent of value as with engine oil? That is the reason I always torque the heads on before installing camshaft. If cam has any drag, it will heat up and GRAB the bearing, spinning it in bore and wearing bore. Best of luck.---Lee

 

[TurboDave]

Thanks Lee! I was toying with the idea of backing off a little to around 90 ish. My ARP head bolts call for 70 which is a little less that I usually run, but I just might try that also. I usually run 85 on the heads.