arp head studs vs arp head bolts

what is your preference? i am lifting a head under boost and blowing boost into the cooling system.:notnice: i know the first step is denial... i dont have a hg problem. i do. i built racing engines for years and used studs and bolts. i understand the physics of both with clamping pressures. give me your opinions. 6 psi novi 1000.:shrug:
 
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because a bolt is pulling more at the threads in the block, and a stud is making that more solid, re-distributing that load to the nut. when you put a stud in it's just more solid into the surface already, rather than threading it in after the fact which is what your doing when you put a bolt in.

studs might help but i'd still wonder why your lifting a head at 6psi when your supposed to be able to run 9psi conservatively with out a problem......
 
A blot will twist as its tightened,thereby requiring more torque to get the same effect clamping force (well,theoreticaly) as a stud.

timewarperped,that would only really apply if the bolt was so short that it started to make head contact with the surface as soon as the threads started.

What kinda gasket is it btw?If its a standard felpro thats your problem.
 
You can reuse bolts 3x according to ARP.

I use bolts and I'm going to reuse it when the engine goes back in the car. I'm not worried.

Your probably having problems because you have stock bolts (old/factory) and have stock head gaskets maybe?

If you have the extra dough, get the studs. If you don't the bolts will be fine for that combo...

Good Luck!
 
5spd GT said:
You can reuse bolts 3x according to ARP.

I use bolts and I'm going to reuse it when the engine goes back in the car. I'm not worried.

Your probably having problems because you have stock bolts (old/factory) and have stock head gaskets maybe?

If you have the extra dough, get the studs. If you don't the bolts will be fine for that combo...

Good Luck!

I ran ARP bolts at 12 psi without issue.

Torque to yield bolts are not torqued until they yield.... despite what it sounds like. Bolt manufacturer's recommendation will generally only be 60-70% of yield which means the bolts can be reused. How many times is sort of a grey area that isn't set in stone. One way to know is by measuring the length of the bolt before using it and keeping a note. If the bolt has stretched by more than a thousandth, you shouldn't reuse them. I'm sure ARP knows their bolts. So, if you don't want to be as anal as my always over-engineering butt, then just go by their educated guess.

Chris
 
people forget that bolt tourqe is really not what you are after, it is clamp load, you can get more clamp load for the same tourque out of studs.

o-ring it, that will solve your problems (just to be smart though check to make sure everything is flat too)
 
352Ford2 said:
people forget that bolt tourqe is really not what you are after, it is clamp load, you can get more clamp load for the same tourque out of studs.

o-ring it, that will solve your problems (just to be smart though check to make sure everything is flat too)

Fifth post up from your,I basicly said that...

He doesnt need o-ring the block,just a better gasket.

Get a set of Cometics or the SCE Titan self sealing gasket with the stainless compression ring (very nice gasket).
 
yes... stock longblock never touched with 69k miles. had a bit of detonation while tuning with my speed density setup. that probably killed one of the gaskets. what fel-pro gaskets are you guys using? ordering studs and good gaskets. the good thing is that no oil in water and no water in oil. thanks for the replies