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Author Topic:   head bolts vs studs
posted March 16, 2004 07:39 AM
How much compression and HP can stock head bolts handle and at what point should one decide to go with head studs.

posted March 16, 2004 08:09 AM
I also have the same question for main bolts/studs

posted March 16, 2004 10:33 AM
Personally, I don't trust stock head bolts for anything. Depending on where your engine came from, the bolts could be upwards of 30 years old now. That's asking alot for them. For the price, ARP bolts in all critical areas (main caps, heads and rod bolts) are probably the single biggest thing you can do to improve reliability. With good bolts, the castings/rod forgings become the limiting factor around 500-650 hp and 7000-8000ish rpm.

A brand spanking new stock bolt might be ok if it were made today, but it's just not worth it to me. Metallurgy today is much better than it was 30 years ago.

posted March 16, 2004 11:34 AM
Arp told me that studs and bolts are good long as you can get them to torque to what you want.If you can't get them tight then toss them. rod bolts measure strech but you have to record and keep track of each bolt when they gain .001 free length toss them.

Ego Racing
posted March 18, 2004 06:31 PM
If you ever tried to put the head on the porcupine that an hegine is with studs in it, and god forbid one is not lined up gust right, you will go back to bolts. We have had a few 700hp plus engines we ran ARP bolts in and never had a problem.

posted March 18, 2004 09:19 PM
one thing to remember, if you are going to use studs make sure your machine shop torque plate hone's your block with studs.

xx RACER 96
posted March 19, 2004 02:06 AM
The clamping force is more consistent due to the fine threads of head studs, and you are less likely to pull threads and crack the deck of your block with the use of studs. Good insurance at any hp level.

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