gmpp head bolt history?
gmpp head bolt history? has any body had problems with the GM Performance parts head bolts not being able to hold any torque. I was just trying to torque them down at 65 ft/lbs and they were stretching. I even used one of the flexing wrenches to watch it. and it wasn't making it to 60. before any body asks, I did step it up in incriments. I've used them before on my truck engine, and that was at 80 ft/lbs. this is about my millionth issue with this project.
Are you saying you've used these bolts before and they were torqued to 80 foot pounds and you're trying to use them again?
If yes, they were junk when they were torqued beyond 70 foot pounds.
The max on a stock bolt is 70 foot pounds. They will stretch at not much more.
You shoulda went with the insurance of ARP head (and main cap) bolts.
http://www.348-409.com/torquesm.html
If yes, they were junk when they were torqued beyond 70 foot pounds.
The max on a stock bolt is 70 foot pounds. They will stretch at not much more.
You shoulda went with the insurance of ARP head (and main cap) bolts.
http://www.348-409.com/torquesm.html
I've had brand new ones break before I hit 65 ft lbs. a year ago on a project. They did do a warranty claim...for one bolt!!! Junk!!! I've switched to ARP and never looked back.
It was definately brand new bolts, especially since I'm hoping to make some serious power. When I said I used them before, I meant that I used the same product before. GM is going to owe me some head gaskets, I'm not paying for those again. I'm definately going to arp after this. They better not pull a one bolt BS.
I doubt if GM is gonna return your money for head bolts let alone replace the head gaskets for free.
I guess this was issue one million one, eh? Get ARP bolts, new gaskets and don't look back.
Gizmo, good (SBC) head bolts should be able to be re-used. They are not TTY like in the LS series.
I guess this was issue one million one, eh? Get ARP bolts, new gaskets and don't look back.
Gizmo, good (SBC) head bolts should be able to be re-used. They are not TTY like in the LS series.
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Best we can tell LT1s came with both standard and TTY bolts over the years. Would be pretty typical for GMPP to supersede a PN and substitute the later ones when folks order for an older application.
I would not go putting studs in a block bored with bolts.
I would not go putting studs in a block bored with bolts.
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