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Discussion Starter #1
On the torque specs for a BBC using ARP headbolts... Now my Chiltons book said 80pounds but did some checking and it seem it's more like 75 pounds long bolts and 65-68 short bolts.

I torque'd everything to 80.

Who can give me the correct torque for these heads with ARP bolts..

Everyplace i look i see conflicting #'s:|err
 

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Don't go by the Chiltons book. Use the instructions that ARP gives. There should be different numbers depending on what lube you use too.
 

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Oops!

On the torque specs for a BBC using ARP headbolts... Now my Chiltons book said 80pounds but did some checking and it seem it's more like 75 pounds long bolts and 65-68 short bolts.

I torque'd everything to 80.

Who can give me the correct torque for these heads with ARP bolts..

Everyplace i look i see conflicting #'s:|err
Too late..............The head bolts came with INSTRUCTIONS. Right?....ARPs are not the same as the stockers, so using stock specs is wrong, period. Fastener torque is an industry wide practice in an effort to make it easy for the average DIY guy to stretch the fastener to the proper tensile load. That is why the Chilton, and most other STOCKER books list a different torque value for the long and short bolts. ARPs are not stockers, and the torque value in the ARP INSTRUCTIONS is based on what it takes to get the PROPER bolt stretch for the aftermarket ARP bolts using ARP thread lube. ........So, what do the instructions say?...............MP

PS: BBC head bolts are live to WATER and should be sealed with silicone to prevent leaks, both outside, and inside the valve covers. A leaking head bolt inside the V/cover will pollute the oil, outside leaks are just a pain in the ass. ARP thread lube is not a sealer, and if you oil the threads the silicone won't stick. Both are very good reasons to use STUDS and nuts............
 

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I don't know if it was just the set i got or what but their was no torque ins with them.I got them from ARP's web site.I printed the page out and keep it in the shop.
 

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Too late..............The head bolts came with INSTRUCTIONS. Right?....ARPs are not the same as the stockers, so using stock specs is wrong, period. Fastener torque is an industry wide practice in an effort to make it easy for the average DIY guy to stretch the fastener to the proper tensile load. That is why the Chilton, and most other STOCKER books list a different torque value for the long and short bolts. ARPs are not stockers, and the torque value in the ARP INSTRUCTIONS is based on what it takes to get the PROPER bolt stretch for the aftermarket ARP bolts using ARP thread lube. ........So, what do the instructions say?...............MP

PS: BBC head bolts are live to WATER and should be sealed with silicone to prevent leaks, both outside, and inside the valve covers. A leaking head bolt inside the V/cover will pollute the oil, outside leaks are just a pain in the ass. ARP thread lube is not a sealer, and if you oil the threads the silicone won't stick. Both are very good reasons to use STUDS and nuts............
Hey moneypit, you ever try SWAK? That's what we use and works great!!
 

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It's what we do
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PS: BBC head bolts are live to WATER and should be sealed with silicone to prevent leaks, both outside, and inside the valve covers. A leaking head bolt inside the V/cover will pollute the oil, outside leaks are just a pain in the ass. ARP thread lube is not a sealer, and if you oil the threads the silicone won't stick. Both are very good reasons to use STUDS and nuts............
Only on the Mark IV blocks. The Gen V & VI are blind holes and use lube only.
Just FYI
 

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My bad, need to learn how to read. Those numbers are what I use for with studs.
 

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Discussion Starter #12
2savage4you, you live in Bullhead?

I've always used 70 ft/lbs with oil unless it's specified otherwise!!

Yes i do..

70 ft/lbs on the shorter bolts too....

Thanks, this is a big help, i did torque to 80/85 tall and 60/65 short and i used Jegs thread sealer... But im gonna tear into it and check it out one last time..

Thanks again:)devil
 

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E-7 Sheepdog (ret)
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sooooooooo..... Does anybody know what the torque specs are ???

I cant seem to find em and they were not in with my bolts
Hmmm,. that's main bolts sized, got to dig more.

Sorry.
 

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Well, according to ARP's website:
1/2"-13TPI (thread per inch) bolts, 180,000 PSI tensile ("High Perf" series) 111 pounds w/ 30-wt oil. 88 pounds w/ ARP lube. 17,000 pounds preload

1/2"-20TPI is 122 pounds and 95 pounds, oil and ARP lube. 19,100 pounds preload

The "Pro series" are a 220,000PSI tesile fastener.
same sizes and lubes respectively:
1/2"-13TPI bolts - 138 pounds / 110 pounds 21,200 pounds preload

1/2"-20TPI bolts - 152 pounds / 119 pounds 24,000 pounds preload
Standard Chevy head bolts are 7/16", NOT 1/2"!!!!

Absolutely do not use those specs on 7/16" BBC head bolts!!!
 

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E-7 Sheepdog (ret)
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Dial 1-800-826-3045 and have the P/N of the bolt kit you have.
 

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Standard Chevy head bolts are 7/16", NOT 1/2"!!!!

Absolutely do not use those specs on 7/16" BBC head bolts!!!
I guess that's why I listed the fastener size.

Had mains on the mind.

Back into the catologue.

7/16-14 73 pounds oil, 58 pounds ARP lubed, HP fasteners

7/16-20, 80 pounds oil, 62 pounds ARP lubed, HP fasteners

7/16-14, 91 pounds oil, 72 pounds ARP lubed, PRO fasteners

7/16-20, 100 pounds oil, 78 pounds ARP lubed, PRO fasteners
 

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The website or package should be able to supply correct information. BBC main studs or bolts would be 1/2", but only if someone redrills and taps the block do 1/2" head bolts or head studs get used on a Chevy big block.

I have the spec sheet from a set of 180,000 psi 7/16" BBC head bolts, but will not post since I don't know what you have, and ARP does make different sets. I think, but am not sure, that most of their Chevy cylinder head fasteners have "undercut" short bolts or studs so that the same torque spec gets used on all.

They do show a 13.334% increase in their spec if you use oil instead of ARP moly lube on this particular set of 7/16" bolts this sheet came from.
 

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I guess that's why I listed the fastener size.

Had mains on the mind.

Back into the catologue.

7/16-14 73 pounds oil, 58 pounds ARP lubed, HP fasteners

7/16-20, 80 pounds oil, 62 pounds ARP lubed, HP fasteners

7/16-14, 91 pounds oil, 72 pounds ARP lubed, PRO fasteners

7/16-20, 100 pounds oil, 78 pounds ARP lubed, PRO fasteners
While that may be something they list, it does not match the sheet that I have from the most recent set of ARP BBC head bolts that I put in an engine, and is the reason I did not post any specs.
 

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Yes i do..

70 ft/lbs on the shorter bolts too....

Thanks, this is a big help, i did torque to 80/85 tall and 60/65 short and i used Jegs thread sealer... But im gonna tear into it and check it out one last time..

Thanks again:)devil
I need to learn to read, I torque the studs to 70 not bolts.

Right on. My oldman's shop is down in the Valley. My old stomping grounds!!!
 
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