LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Splayed 4 bolt tq#

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Old 09-05-2012, 08:59 PM
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Default Splayed 4 bolt tq#

Needing the TQ numbers for the inside and outside bolts. ARP inside studs and ARP outside bolts.
Old 09-05-2012, 09:20 PM
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Fastener torque is specific to the fastener. I don't know if ARP has multiple grades of bolt for that application but just incase I would look it up on their site or at least post the PN you are using here.
Old 09-10-2012, 12:58 PM
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according to ARP a 7/16 stud is tq to 70 ftlbs, and outer splayed 3/8 bolts to 45 ftlbs. Does that sound right? The Haynes ask for 77ftlbs for stock main cap bolts.
Old 09-11-2012, 07:40 AM
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every splayed conversion ive done with studs they all went to 80ft/lbs with moly lube.....in reality you should be torquing it to whatever your machine shop did when they cut the mains......any more you can distort the housing.....arp used to want 100ft/lbs which is what i did on my inital build....upon dissasembly two years later to check it over i found the mains were oblonged a bit from excessive torque........conciquently arp lowered their rating to 80lbs just about when i saw this......i run 80
Old 09-11-2012, 09:40 AM
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The "what lube" and "what were they torqued at for machining" are very good points.
Old 09-11-2012, 10:30 AM
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Originally Posted by quik95lt1
every splayed conversion ive done with studs they all went to 80ft/lbs with moly lube.....in reality you should be torquing it to whatever your machine shop did when they cut the mains......any more you can distort the housing.....arp used to want 100ft/lbs which is what i did on my inital build....upon dissasembly two years later to check it over i found the mains were oblonged a bit from excessive torque........conciquently arp lowered their rating to 80lbs just about when i saw this......i run 80
100 did seem a tad high to me. I right at 80 on my motor.
Old 09-11-2012, 04:06 PM
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I wish I had the info but the machine shop that did my first build is no longer in business. I think I'm just gonna go with 77 on the bolts and 45 on the splayed with arp lube. Anyone think that's a bad idea? Or have another suggestion?
Old 09-11-2012, 05:50 PM
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I would also go with ARP's specified torque for the size/thread of the fastener. They rate their fasteners by how much they stretch, not how much they clamp. Purchase and use their Ultra Torque thread lube-it's better than any other thread lube on the market.

Your outer bolts are 3/8 inch??
Old 09-11-2012, 07:36 PM
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I think most of us understand that torquing a bolt is intended to stretch it some BUT at the same time the point quick95lt1 made was that there are other variables far as lube and what the block was machined at. I would also add that maybe a production block just distorts too much at 100ft. lbs. He also said ARP themselves lowered the suggested torque.

Far as the Ultra Torque thread lube I have heard some negatives about parts being damaged before torque was reached because it was so slick. Which brings us right back to trying to replicate whatever the machine shop did being the best bet

If 80 with moly was ARPs spec a couple years back when this was built before the Ultra Torque lube came out then that would be the best bet. If really worried could torque it and have the mains mic'd.
Old 09-11-2012, 08:10 PM
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Originally Posted by 96capricemgr
I think most of us understand that torquing a bolt is intended to stretch it some BUT at the same time the point quick95lt1 made was that there are other variables far as lube and what the block was machined at. I would also add that maybe a production block just distorts too much at 100ft. lbs. He also said ARP themselves lowered the suggested torque.

Far as the Ultra Torque thread lube I have heard some negatives about parts being damaged before torque was reached because it was so slick. Which brings us right back to trying to replicate whatever the machine shop did being the best bet

If 80 with moly was ARPs spec a couple years back when this was built before the Ultra Torque lube came out then that would be the best bet. If really worried could torque it and have the mains mic'd.
I use the regular ARP stuff not the Ultra, I guess they revised the formula or something along those lines. I just use the stuff that I know works.



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