ARP Head Stud Torque Specs???
TECH Resident
Joined: Oct 2006
Posts: 993
Likes: 173
From: Euless, TX
I just put ARP studs on my SBC 383. I used their older instructions for the same stud and material type. I refuse to crank them to 80 ft/lbs from the dozens of people that have pulled studs from the relatively frail factory block decks as well as looking at a block deck of a LT1 that had run 1-2 years with studs torqued at 80 ft/lbs. The LT1 block had nickel to quarter sized dimples around the stud where the block deck had been distorted from the pull of the studs at 80 ft/lbs. The older instructions showed 65 ft/lbs with aluminum heads and 70 ft/lbs with cast iron heads. I went to 65 ft/lbs. Even at 65 ft/lbs it will have more clamping force than the factory style head bolts.
I just put ARP studs on my SBC 383. I used their older instructions for the same stud and material type. I refuse to crank them to 80 ft/lbs from the dozens of people that have pulled studs from the relatively frail factory block decks as well as looking at a block deck of a LT1 that had run 1-2 years with studs torqued at 80 ft/lbs. The LT1 block had nickel to quarter sized dimples around the stud where the block deck had been distorted from the pull of the studs at 80 ft/lbs. The older instructions showed 65 ft/lbs with aluminum heads and 70 ft/lbs with cast iron heads. I went to 65 ft/lbs. Even at 65 ft/lbs it will have more clamping force than the factory style head bolts.
TECH Resident
Joined: Oct 2006
Posts: 993
Likes: 173
From: Euless, TX
I totally agree with you on a gen1 or gen2 sbc block. The head bolts go into the deck where the water jackets are, making the bolts/studs pull against a much weaker area of the deck. That’s not the case with the gen3/4/5 LS and LT platforms. The headbolt holes are blind. The headbolt holes go deep into the block, which allows the bolts/studs to pull from the strongest area of the block. Makes for a much more robust assembly when heads are torqued. Although distortion will be present here, it’s much less than what was seen in the gen1/2 sbc blocks, even in the bow-tie versions. I’m sure your aware of this, I’m just trying to keep this thread about the LS platform. As said above many times, it’s always best to consult the ARP instructions when using their products.
