GPA951s

So I was on the fence about what studs to use for my new engine.. Raceware? Stock? Arp? I have two engines in my other cars with Raceware, the last time I put my "Sleeved" engine together I set the Torque at 95Ft Lbs even though Raceware called for like 65... I thought that 65 was way to low. (3 seasons now and no issue) I found a nice set of ARP studs for a great price so I decided why not? They came in a really nice blow molded tray and I was looking over the installation instructions.. ARP Calls for the head to be Torqued in 3 stages and the ultimate value being 100Ft Lbs... I also noticed that the Stud itself is a bit longer than stock and has more threads than the stock studs, which means at the proper installed height they are going deeper into the block engaging more of the aluminum.
I took an old stud and cut Grooves into it (like a tap) and the flattened the face of it like a blind tap, and took a bunch of old lock-tite out of the holes.... That tells me that the studs can in fact engage deeper into the threaded holes.

Anyway, Just thought Id post this info and share with the rest of the community..

refresh951

I do not think I would go with 100 ftlbs, as that is very close to pullout. I have been using 87 ftlbs with a Cometic and ARP studs with good success.

GPA951s

Yup That's what i was thinking... BTW I bought those ISKY Valve springs and just got them all set up on Saturday.. Cant beat em for 100 bucks.. The card that came with them said they were rated at 130Lbs at 1.700... I set them to 1.614 and was around 140-ish.. Thanks for your webpage..

V2Rocket

few folks i've heard from have said 105 ftlbs for the ARPs.
guy i bought my current engine from did/said the same thing...head's still attached so far

wildcat077

Yeah , that's what ARP recommended ( 100 ft/lbs ) when i built my engine last year. I figured it was a lot , and even the tech at
Cometic said that if ARP calls for it then it should be good.

I did like GPA and also found some dried out crud / loctite ? in the block after i cleaned out the treads ...
Although after i installed the studs , i measured how much they were all protruding from the block and they were all
within .030 so i was happy with that.

Cheers
Phil

Voith

This is with your 16v head? I also have arp bolts and was scratching my head when I saw 100ftlbs.

333pg333

To me the potential issue isn't with ARP's specification but of these 25+ year old Alu blocks with very little knowledge of their history. ie how many times might the block gone through some metallurgical challenges via overheating etc.
So I'd tread with caution and not automatically assume that the stud manufacturer is aware of the block it's going into. We had a stud pull out on one of the blocks in the past and went down the path of making serts to try and 'fix' the situation.
That did work but might have got lucky too.