Headbolt Torques?
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Joined: Feb 2008
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From: Pearl City, Hawaii
Headbolt Torques? I've searched the threads and found 2 different torque #'s and techniques. As per Haynes the torque for the "Stock" headbolts is 22 ftlbs, I looked on here and found guys saying 1st torque to 25 then 55 then final @ 65. Well I tried it with some Fel-pro bolts and that definitely was not the way to go! I can only guess that the 65 would be for aftermarket headbolts? Any insight would be greatly appreciated, I plan on pulling the Fel-pro bolts out one by one and replacing with some ARP's. What do you guys think?
The stock head bolts are a torque to yield (TTY) head bolt. Which means there isn't a number for a final torque spec, but rather a certain number of degrees. (I don't remember exactly what it is right now, I would have to look it up.) For aftermarket head bolts I usually torque, in the proper sequence, to 25 - 45 - 65. Never had w problem with that yet.
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Joined: Dec 2008
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From: Little Rock, AR
I've searched the threads and found 2 different torque #'s and techniques. As per Haynes the torque for the "Stock" headbolts is 22 ftlbs, I looked on here and found guys saying 1st torque to 25 then 55 then final @ 65. Well I tried it with some Fel-pro bolts and that definitely was not the way to go! I can only guess that the 65 would be for aftermarket headbolts? Any insight would be greatly appreciated, I plan on pulling the Fel-pro bolts out one by one and replacing with some ARP's. What do you guys think?
That is just the starting point for the torque/angle method used on later year LT1s (the bolts are not actually TTY bolts).http://shbox.com/ci/head_assy.jpg
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Joined: Apr 2007
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From: Kempner, TX
The bolts aren't TTY it's just a different torquing procedure.
Be sure what spec YOUR bolts call for because the torque specs do change depending on the bolts or (in the case of stock bolts) the year of the engine.
Even the ARP head bolts call for different torque spec depending on the lubricant used; 30W engine oil Vs ARP's lubricant. I always use the torque spec the bolt manufacturer recommends.
Jake
Be sure what spec YOUR bolts call for because the torque specs do change depending on the bolts or (in the case of stock bolts) the year of the engine.
Even the ARP head bolts call for different torque spec depending on the lubricant used; 30W engine oil Vs ARP's lubricant. I always use the torque spec the bolt manufacturer recommends.
Jake
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From: Kempner, TX
This issue has been surfacing more and more lately. I'd like you to cite the source for your claim that the stock head bolts are TTY. Seems that many read the degree method of tightening head bolts and assume that means the bolts are TTY.
I've thoroughly searched my 96 Vette FSM and I have not been able to find any mention by GM that the stock LT1 head bolts being TTY.
Jake
I've thoroughly searched my 96 Vette FSM and I have not been able to find any mention by GM that the stock LT1 head bolts being TTY.
Jake
I stand corrected and my deepest sympathies and appologies go out to anyone who I may have offended or hurt their feelings.
With that being said, I have never used / reused any stock or torque/angle bolts so I guess I really should have not commented on that part of it.
Chill man, no need to get bent out of shape here man. I was simply reciting what I have heard out and about, and read on different forums. Like I said previously, I have never actually used them and I do not have any "specific source to site." Once again, my appologies..........
Shoebox....Thank you for showing some class and decency on the correction.
With that being said, I have never used / reused any stock or torque/angle bolts so I guess I really should have not commented on that part of it.
Shoebox....Thank you for showing some class and decency on the correction.
