When do you need head studs?

[Josparkz]

What is a good rule of thumb, horsepower wise, for needing studs? I put some in my engine perhaps 15 years ago (ARP) and one recently broke. Now I'm finding a lot of other people have had them break. ARP says "hydrogen embrittlement". I see some people get 400, 000 miles on their stock headbolts and gaskets, with as much as 300 H.P. I may have 325 H.P. on mine. I'm having a lot of trouble going for a new set of studs when a broken one just is going to cost me some costly repairs. How much horsepower will bolts supposedly stand up to?

 

[BigPapa]

As I posted in your other thread, I'm a fan of factory head bolts until you get into very high HP builds. My '95 engine has over 550K miles on it and at one time was over 400HP and the head's never been off.

 

[Josparkz]

As I posted in your other thread, I'm a fan of factory head bolts until you get into very high HP builds. My '95 engine has over 550K miles on it and at one time was over 400HP and the head's never been off.

About how long did you run it at 400 horse, and what do you usually run it at?

 

[SSage]

40 psi for occasional pulls has been safe for me for many years. So far that has worked for about 100,000 miles off and on, my truck didn't stay stock for long. I also don't run it hot much, no more than 1200 on egt when towing. So far I'm still using the original exhaust manifold in my 95.

 

[BigPapa]

About how long did you run it at 400 horse, and what do you usually run it at?

Close to a year and @ 35K miles. I had some DD3’s, a Sled Puller 66, and some pump work. It was before the ‘95 got totaled and I was running the 5-speed. I was commuting 100 miles a day, no interstates, 55mph speed limit max. I could hit almost 50psi boost. Then the truck got totaled and I transplanted the engine into my ‘98.5 QC with an auto. Sold the SP66 and the injectors and went back to my 215’s and an HE351.. It’s gated at 35psi.

 

[Josparkz]

I only have about 32 lbs boost. I should probably be okay putting bolts back in.

 

[Ozymandias]

Well, 32psi is what mine makes from factory, with bolts from factory, so it must be good to go right?

 

[Josparkz]

Well, 32psi is what mine makes from factory, with bolts from factory, so it must be good to go right?

Should be.

 

[Joseph Donnelly]

I found through experience that 800 HP with 28 degrees of timing and 60 psi boost, stock head gasket, was too much for stock, re-used head bolts. The timing was at least as much a factor as anything else.

 

[Josparkz]

I found through experience that 800 HP with 28 degrees of timing and 60 psi boost, stock head gasket, was too much for stock, re-used head bolts. The timing was at least as much a factor as anything else.

I had someone set the pump timing too much once. That took out the head gasket within 100 miles . That was ugly.