Budman II

iTrader: (1)

Does anyone have the rod bolt stretch spec for the ARP bolts used with the Eagle I-beam rods? These are the cap-screw bolts. I found torque values on Eagle's site for 63 ft lbs, but want to use stretch instead.

Thanks!

mike tkach

iTrader: (3)

the 8740 bolt stretch is 5.9 to 6.3.arp sais 63 lbs of torque will give you the desired stretch when useing arp ultra lube.

MER Performance

ARP 2000 or L-19 ?
Wait a minute; do you have a I beam SIR rod, or a H beam?

Budman II

iTrader: (1)

Mark, they are the I-beam, not the H. They are not the L-19, they are 8740, 1.75" length under the head, 7/16 head and thread size, IIRC.

Budman II

iTrader: (1)

I have read several threads that indicated that it took considerably higher torque to get that stretch value, even with the ARP lube. I torqued to 63 a couple of times, and followed up with a stretch gauge to .0055, and it sure felt like I was pulling more torque, although I don't have a torque extender to put a torque wrench on it while using the stretch gauge.

MER Performance

Mike, is correct. even for the SIR rods the stretch is .0059-.0063. Just spoke with Eagle.
It will require more torque, even with the ARP lube to get the stretch. I would take it to .006 & stop.

Budman II

iTrader: (1)

That is exactly what I am going to do. Thanks guys!