3rdCoastPowerSports

iTrader: (5)

installed new ARP 8740 7/16 1.75" rod bolts into new forged rods. I tightened both bolts first to 15 ft/lbs then tightened the top bolt to 63 ft/lbs and then the bottom bolt to 63 ft/lbs. I know my torque value is correct im asking about my sequencing, do you see any issues with the way i did this or am i over thinking things again?

bww3588

iTrader: (49)

I thought the torque spec for them bolts was 45 ft lbs. Correct me if I'm wrong.

3rdCoastPowerSports

iTrader: (5)

45ft/lbs is for the 3/8 8740 bolts. I got the bolt specs from scat

Steve - Race Eng

iTrader: (1)

http://arpinstructions.com/index.php

Enter the bolt part number and a pdf instruction spec sheet is presented with the correct method to tighten that particular bolt.

Always check the rod big end for size and out of round when replacing bolts.

kpadlina

63 ft lbs sounds REALLY high.....

KCS

iTrader: (20)

It's not. 75ft-lbs is typical on a 7/16" 8740 bolt.

3rdCoastPowerSports

iTrader: (5)

Man i will be honest I am pretty frustrated with ARP... they cant seem to get their **** strait. call them 5 times and ask the same question about torque spec of a certain bolt and you will get 3 or 4 different answers.... I actually went down the street SCAT walked in and chatted with a tech. 63 ft/lbs is/was the correct torque spec for my bolts.
funny you say 75 ft/lbs on a 7/16 8740 because when i called ARP that's what they told me the 7/16 2000 torque out to.
I love ARP but damn they need to be more consistent on their tech advice

RezinTexas

My spec sheet that came with my Eagle rods confirms what you say here.

63 for 8740
75 for 2000

both @ 7/16 dia

crainholio

iTrader: (2)

Sounds like this is the first time you've torqued them.

Which means you didn't torque them and take measurements of the big-end diameter before installing them. Or at least use Plastigage.

Failure guaranteed.

KCS

iTrader: (20)

Yeah, that's right. I was thinking ARP 2000's.

In my experience, the best way is to use a stretch gauge. It's not uncommon to have to increase torque to get the recommended stretch. The ARP 2000 bolts in my stock rods for example had to go to 55ft-lbs.

The way I read it, he hasn't installed the rods, just the bolts into the rods.

chrisfrost

iTrader: (8)

Yes my ARP sportsman rod bolts I brought them to 58lb. ft. before I detected .0002" stretch .

RezinTexas

+1000 for a stretch gauge. I'm even going the extra expense of adding a Mitutoyo .0001 dial indicator for it.