Lots of info on this out there but everyone has their different opinion. Question is on cylinder heads when does it warrant ARP studs, ARP bolts, then GM bolts. I feel like ARP bolts and GM bolts essentially can do same thing it just ARP bolt can be reused is only plus. I feel like ARP studs are needed when you get above 700HP or something like that. Or if you add boost do you need ARP bolts, many people running up to 600HP on GM bolts. GM bolts are Torque to yield so they need to be tightened properly.

 

Good question and I've wondered this myself.

ARP: Reusing them is the only benefit that I can think of at stock or for slight/med. modified engines. Cons would obviously be cost. Then there's some stories of guys snapping them when attempting to torque them. 🤷 I guess that brings another point that to install them, they are not TTY, but rather torqued to a specified torque setting. Not sure of the difference between bolts vs studs. 🤔

Then there's the YT guys saying they've re-used the OEM ones! LOL

 

I will never reuse OEM head bolts, throw them in bolt bin and use them around the house. I wouldnt expect GM to use ARP bolts when they build like a z06 or zl1. I bet they do use their own head studs on vehicles like that though. I am sure ARP is better and the material used but doesnt warrant double the cost, especially when arp had studs are 300 pretty much. If I was doing a rebuild and didnt have to buy anything new, just a refresh of the engine then yes I would throw ARP in.

 

Here is my take on it.
If you plan to never go in the engine or change the heads, Use OEM.
If there is a chance You might change something, At least use ARP bolts.
If your going boosted or plan on spraying it where you will see increased Cylinder temperatures and pressures, Consider going studs.

 

My take is studs for max effort or high boost. Bolts for any NA engine or a boosted app that isn’t crazy.

OEM never.

 

I use OEM bolts for DOD deletes.
ARP bolts for most everything that has a aftermarket camshaft and bolt ons.

ARP studs for boost/nitrous setups.

 

So I am going to keep kicking this can down the road. If I wasnt going to boost I wouldnt be as worried about it, throw new Gm bolts in and done. But I was almost convinced to get arp studs until I started reading reviews at some places. Almost half the reviews are people pissed about broken studs. Now thats not factoring in the people who have had good experiences and most no one posts reviews. But the fact you pay over 300 for bolts, advertised as best out there, best material, and you still have people breaking them when doing proper tightening. I am sure if I got a set it would be fine, but hell I dont know. Part of me says stay with GM bolts call me crazy

 

Gm bolts here, I’m only at 9 #s though. Daily drive it all day not to and from work but all day, it’s my service truck. Lol. No issues here and I’ve put about 75k on it boosted.

 

What they don't mention is that they failed to read the instructions when installing the studs. I am not saying its not possible to get a defective product Hell I have seen them ship nuts that didn't get the threads cut. But these people are clearly doing something wrong. Most of the time they torque the stud in the block which is a no-no... Others are using Cheap torque wrenches that are not calibrated properly or don't apply torque properly through out the torque range.

My machine shop has never broken a stud and they do a variety of blocks with main and head studs.

I have never Broken a stud either and I usually torque cycle mine atleast 3 times before the engine is finally assembled.

 

I agree with FB.
I send my torque wrench off every 6 months to get calibrated. So far it's never been off by any crazy amount over the past 6 years.
Ive used prolly 45 sets of arp main studs, 50-52 sets of arp head studs and 20ish sets of arp head bolts this year and no issues. And 15ish sets of Felpro brand TTY head bolts.

Knowing how to use a torque wrench and what threads/washers to use the moly on helps too.