Torque spec for non-factory screw-in rocker studs
10-07-2010, 11:46 AM
#1
Pro
Thread Starter
Torque spec for non-factory screw-in rocker studs
Hello Folks,
My SBC heads have replacement screw-in rocker arm studs, the shoulderless kind (not OEM).
What would be the torque spec for these studs?
I need to re-torque and re-seal all of them, and I also need a recommendation for a threadlocker. I was thinking of Loctite 242; any other ideas?
Thanks in advance.
My SBC heads have replacement screw-in rocker arm studs, the shoulderless kind (not OEM).
What would be the torque spec for these studs?
I need to re-torque and re-seal all of them, and I also need a recommendation for a threadlocker. I was thinking of Loctite 242; any other ideas?
Thanks in advance.
Last edited by kbuhagiar; 10-07-2010 at 05:55 PM.
10-07-2010, 04:46 PM
#2
Team Owner
Member Since: Oct 2000
Location: Washington Michigan
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The link doesn't work, but the cylinder head end of those studs should be 7/16" threads; 50-60 ft-lbs. should be about right. 
10-07-2010, 08:29 PM
#3
Le Mans Master
Be very careful when torquing "shoulder-less" studs...
Notice the raised ridge at the top of the threads (head side). If you torque them a bit too much this ridge acts as a wedge and it can very easily split the boss. Many heads back in the day had their boss' cracked because of these studs. Folks liked them because you don't have to machine the boss to install them, just tap the boss. But in my opinion it isn't worth the small savings to risk ruining a head.
If you are real lucky when one does crack, you may be able to machine the boss' and then use these studs...
If you're not lucky, and many were not, well, you can always buy another head...
Good luck... GUSTO
Notice the raised ridge at the top of the threads (head side). If you torque them a bit too much this ridge acts as a wedge and it can very easily split the boss. Many heads back in the day had their boss' cracked because of these studs. Folks liked them because you don't have to machine the boss to install them, just tap the boss. But in my opinion it isn't worth the small savings to risk ruining a head.
If you are real lucky when one does crack, you may be able to machine the boss' and then use these studs...
If you're not lucky, and many were not, well, you can always buy another head...
Good luck... GUSTO
Last edited by GUSTO14; 10-07-2010 at 08:32 PM.
10-07-2010, 08:42 PM
#4
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I've broken shouldered rocker studs that didn't have an adequate radius at the shoulder. I'd be mighty wary of using shoulder-less studs (and how would you torque them, anyway?)
If you want to run screw-in studs, have the heads properly machined and get good stuff.... ARP studs. I've never broken one of these.
Jim
If you want to run screw-in studs, have the heads properly machined and get good stuff.... ARP studs. I've never broken one of these.
Jim
10-07-2010, 10:42 PM
#5
Pro
Thread Starter
Be very careful when torquing "shoulder-less" studs...
Notice the raised ridge at the top of the threads (head side). If you torque them a bit too much this ridge acts as a wedge and it can very easily split the boss. Many heads back in the day had their boss' cracked because of these studs. Folks liked them because you don't have to machine the boss to install them, just tap the boss. But in my opinion it isn't worth the small savings to risk ruining a head.
If you are real lucky when one does crack, you may be able to machine the boss' and then use these studs...
If you're not lucky, and many were not, well, you can always buy another head...
Good luck... GUSTO
Notice the raised ridge at the top of the threads (head side). If you torque them a bit too much this ridge acts as a wedge and it can very easily split the boss. Many heads back in the day had their boss' cracked because of these studs. Folks liked them because you don't have to machine the boss to install them, just tap the boss. But in my opinion it isn't worth the small savings to risk ruining a head.
If you are real lucky when one does crack, you may be able to machine the boss' and then use these studs...
If you're not lucky, and many were not, well, you can always buy another head...
Good luck... GUSTO
I've broken shouldered rocker studs that didn't have an adequate radius at the shoulder. I'd be mighty wary of using shoulder-less studs (and how would you torque them, anyway?)
If you want to run screw-in studs, have the heads properly machined and get good stuff.... ARP studs. I've never broken one of these.
Jim
If you want to run screw-in studs, have the heads properly machined and get good stuff.... ARP studs. I've never broken one of these.
Jim
I don't necessarily want to run screw-in studs, I'm merely playing the hand that was dealt to me. The car came this way.
I just want to get the valve train squared away and get 'er back on the road without having to pull the top end,
as I currently cannot devote sufficient time or resources to pull the heads.
Thanks again for the input.
