I got my pro comp ebay head studs in. Getting ready to install them this week.

What is the initial torque spec when you install them into block??

I get the three passes up to 70 ft.lbs

What about before that threading them into block before installing heads?

 

ARP recommends hand tight only. Carroll Smith recommends threading them all the way in, and then backing out 1/2 turn or so.

 

Go with arp's they are loosely based off that

 

I will follow arp only torque to 70fl lb's. Had a hard time imagining hand tight as an initial spec.
http://arpinstructions.com/instructions/234-4110.pdf

 

I personally wouldn't recommend that you use the pro comp or ebay studs. I used a set on my 408" build and while torque them down to 70ftlbs, I snapped one of the studs 4" down into the block. It was a nightmare trying to get the broken stud out. I will never cheap out on hardware again. I will only use ARP from now on. I understand that they are a great price but for the headache that was cause by this its not worth it to me. Just my opinion and nobody has to listen either.

 

I find it hard to believe you snapped a head stud,
not saying it isn't possible, but those are Chromoly, and 190,000 psi rated!

 

Believe what you want bit I will knot use them again it was torquing to 70ftlbs!!!

Here is a picture once I got the broken part out

 

I bet that wasn't fun.
Ron

 

Hell no it wasn't, I was one pissed SOB!!! It actually came out easier then I though it would but still pissed me off!

 

I came out fine on my cheapos at 75 ft lbs. but I took the time to carefully rework any threads that were tight or nicked with a small file before installing.

I admit that I was waiting for one to snap. Also, my block is later so none of those really long ones.

Every time my bro stops by to visit he cups his hand around his ear and says "just heard another Pro Comp stud snap)
:-)

I hear Thompson Motorsports has a set now that are nice and cheaper than the ARP.

 

Improper torque on a head stud/bolt is just asking for a blown head gasket. If you're worried that they'll snap just by torquing them down, what do you think is going to happen when cylinder pressures get high?

Never use cheap parts - they're too expensive.

ARP fasteners are expensive. You get what you pay for (if you're lucky).

 

He meant the stud "hand tight" in the block. He's correct.

 

I’ve broken 3 arp studs in the block at the top of the threads. I have the correct tools to get them out. I switched to Chinese studs because I couldn’t shell out another 400 some odd dollars for the arp. They need to be torqued and lived properly, no extension on the torque wrench. The point I’m trying to make is the arp will break too. Way easier than you think they will. I fact try putting them at 85 foot pounds. 2/5 will snap. 120,000 blah blah blah is the clamp strength not the sheer strength. We’ve seen success with Chinese studs at 30 psi boost for many passes. Quality torque wrench that is properly calibrated and they are all the same!

 

You need to sand the bottom side of the washers were they meet the cylinder head. If they spin you will overstretch the bolts.
Been there...
and this thread is 6 years old