Bulk ARP bolts torque spec
05-08-2012, 04:18 PM
#23
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On page 24 of this PDF from ARP, they have a fastener torque chart. In your case 20 ft lbs with their lube, and 25 ft lbs using 30 weight motor oil. Now like said earlier, follow the specs from the maker of the fasterner. I used ARP head bolts a couple weeks ago for my ls1 heads. This torque value is much higher than the torque valve your looking to use. Worked out fine for me, I would use a 2 pass method, 11 ft lbs the first pas, 20 the second pass using ARP moly lube. With an aluminum block its all in the prep, chase the threads, use a can of compressed air ( like for computers) clean the threads, use paper towels if water could be in there and use a small vacuum to vacuum holes also. My friends always think I'm going over board, but I've never stripped a thread or broke a bolt. On the cam, cam plate and oil pump, I have reused the stock bolts with loctite also, with no issues. Here's the link.
http://www.google.com/url?sa=t&rct=j...6-bcOv9SDmQd4A
http://www.google.com/url?sa=t&rct=j...6-bcOv9SDmQd4A
05-08-2012, 04:57 PM
#24
Guys, look at it this way:
ARP makes fasteners that are rated to a specific stretch which they've determined and published torque specifications for. These numbers are for a best case scenario, with the fastener threaded into a fixture or nut equaling the strength of the fastener through what the material is or thread depth engagement.
Those are their numbers and they're gonna stick to them.
Now, if you're dealing with an aluminum block with a limited thread depth engagement, it would be wise to go with the maker's torque spec, in this case GM. Otherwise, attempting to torque them to ARP's specified stretch numbers will in all likely hood result in you pulling the threads out of the block.
I'd also say that there's too much being made here about these smaller fasteners. Use the better ARP bolts. Torque to the GM specs. Use locktite to be sure nothing loosens up unless you want it to.
ARP makes fasteners that are rated to a specific stretch which they've determined and published torque specifications for. These numbers are for a best case scenario, with the fastener threaded into a fixture or nut equaling the strength of the fastener through what the material is or thread depth engagement.
Those are their numbers and they're gonna stick to them.
Now, if you're dealing with an aluminum block with a limited thread depth engagement, it would be wise to go with the maker's torque spec, in this case GM. Otherwise, attempting to torque them to ARP's specified stretch numbers will in all likely hood result in you pulling the threads out of the block.
I'd also say that there's too much being made here about these smaller fasteners. Use the better ARP bolts. Torque to the GM specs. Use locktite to be sure nothing loosens up unless you want it to.
05-13-2012, 10:44 AM
#25
After Many conversations with ARP....I went a head and trusted them. I torqued the cam retaining bolts to 24 ft lbs. Seem to have held up fine. I had the heads lubed with ultra torque with Blue loctite on the threads. Went slow, in a circular pattern in increments of 10-15-20-24.
Now I feel sick about it lol...Thermal heat expansion and a bolt some day popping out has me losing sleep
Now I feel sick about it lol...Thermal heat expansion and a bolt some day popping out has me losing sleep
05-13-2012, 12:54 PM
#26
While I certainly hope this all goes well for you, I think you're making a mistake.
GM specs these bolts (even for iron blocks) at 18 ft lbs.
As you have an aluminum block, I would worry that with heat cycles, the threads in the block may fail. Aluminum and steel/iron expand and contract at different rates with heat so I think the GM specified numbers is more important in an aluminum block.
If you had an iron block, the higher torque numbers of the better (ARP) fasteners would be OK.
GM specs these bolts (even for iron blocks) at 18 ft lbs.
As you have an aluminum block, I would worry that with heat cycles, the threads in the block may fail. Aluminum and steel/iron expand and contract at different rates with heat so I think the GM specified numbers is more important in an aluminum block.
If you had an iron block, the higher torque numbers of the better (ARP) fasteners would be OK.
05-13-2012, 01:26 PM
#27
While I certainly hope this all goes well for you, I think you're making a mistake.
GM specs these bolts (even for iron blocks) at 18 ft lbs.
As you have an aluminum block, I would worry that with heat cycles, the threads in the block may fail. Aluminum and steel/iron expand and contract at different rates with heat so I think the GM specified numbers is more important in an aluminum block.
If you had an iron block, the higher torque numbers of the better (ARP) fasteners would be OK.
GM specs these bolts (even for iron blocks) at 18 ft lbs.
As you have an aluminum block, I would worry that with heat cycles, the threads in the block may fail. Aluminum and steel/iron expand and contract at different rates with heat so I think the GM specified numbers is more important in an aluminum block.
If you had an iron block, the higher torque numbers of the better (ARP) fasteners would be OK.
05-13-2012, 02:40 PM
#29
Looks to me, your F-'d if you do or you dont!
You don't torque to ARP spec, they will not have the clamping (Spring) force they were designed for.
You do torque, and now thermal expansion will fail the thread!
I may just throw the stockers back in!! What a freakin headache
You don't torque to ARP spec, they will not have the clamping (Spring) force they were designed for.
You do torque, and now thermal expansion will fail the thread!
I may just throw the stockers back in!! What a freakin headache
05-13-2012, 04:05 PM
#30
The bolts you're using are their "bulk" bolts, not designated for a specific application. Head bolts are.
I'd bet that if ARP made a bolt specifically for what you're using them for, they'd be closed to the GM numbers.
These little bolts don't really rely on a stretch for fastening. They just hold things in place and get screwed in tight enough to prevent them from coming out.
Head bolts, main bolts, crank bolts, yes, they need a certain stretch as they're a clamping something critical.
I'd bet that if ARP made a bolt specifically for what you're using them for, they'd be closed to the GM numbers.
These little bolts don't really rely on a stretch for fastening. They just hold things in place and get screwed in tight enough to prevent them from coming out.
Head bolts, main bolts, crank bolts, yes, they need a certain stretch as they're a clamping something critical.
05-13-2012, 04:51 PM
#32
Cam plate retaining bolts were LS1 specific. Thats why it drove me insane that ARP would put the stiff arm and say 24ftlbs and not address my concern with the aluminum block. The only fasteners I'm using in "bulk" is the Oil pump mounting.
