POS Dakota
Anti-Socialist
What's the torque spec for them?
Is it still 85 ft lbs like the factory bolts?
Is it still 85 ft lbs like the factory bolts?
ARP main bolts
- Thread starter POS Dakota
- Start date
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nothingbutdarts
Well-Known Member
if you bought them new the spec. should have come with them. If not I would get on their web sight and look it up.
POS Dakota
Anti-Socialist
There was a sheet of paper in there that said 100 ft lbs...but I dont believe it. lol Doenst that seem like too much????
torque specs depend on lubricant.
POS Dakota
Anti-Socialist
That was with the supplied lubricant.
I have the sheet in front of me.
This is for part 140-5001 mopar 2 bolt main with the small hex heads.
180,000 psi 1/2 inch diameter...
says torque them three equal steps to 100 ft lbs with arp ultra torque fastener lubricant. So that is what I did. lol I torqued them to 40, 70, and then 100 ft lbs...
But what I can't get over is that the factory main bolts as we all know are 85 ft lbs.
What would make ARP decide on 100 ft lbs, vs the factory 85 is what I want to know.
The clearances seem to be unaffected surprisingly enough (I am sure there is a difference, but no difference I could measure anyway), but still I am compelled to ask.
Anyone have any ideas? I'm probably just concerned over nothing, but no question is a dumb one....within reason.
MOPARJ
What can I upgrade now?
The reason for the higher torque figure is to gain clamp load over the OEM fastener. This is one of the main benefits to ARP fasteners; the added clamp load can be beneficial in higher output applications, to help prevent cap walk.
The higher torque is possible through a higher tensile strength material than what is used on the factory fasteners. Additionally, the torque spec listed is not at the yield point of the fastener, so they should be reuseable so as long as the installation procedure is followed and no obvious deformation to the fastener is noticed.
MoparJ knows a bit about ARP products, go with his statement.
POS Dakota
Anti-Socialist
yes I torqued them twice in the prescribed manner during mockup and measurement. They looked like new still so I torqued them one more time for final assembly and called it good.
I was just curious as to why they called for 15 more ft lbs, and what you have said makes perfect sense to me. I looked around but there is very little info I could find on the bolts since everyone uses studs. I wasnt sure I was looking at the right info on the ARP website either.
Then I found the spec sheet today in the garage and felt a lot better about it. I had final torqued these a couple weeks ago IIRC so it wasnt fresh in my mind and after reading up online in a panic and finding nothing last night I was beginning to second-guess myself. I do that a lot.
The thought of them not being near their yield and the fact that the extra clamping doesnt seem to be distorting anything makes me feel convinced I'm fine.
Thanks for the information. I appreciate it!
For anyone else planning on using these, on the rear cap I had to take a tad off the pump and have the cap slightly spot faced for them to fit without hitting. If you were to grind the head down you'd have nothing left to grab.
POS Dakota
Anti-Socialist
When I am not sure, I always ask.
Thanks again guys. I was beginning to think that I screwed up by following ARP's instructions...which is looney, but I needed a reality check!
MOPARJ
What can I upgrade now?
No question is a dumb question; better safe than sorry. I always double check everything I do with the cars. Good luck and hope it works out.
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