Cylinder Head Stud Torque

[SteveW]

I know what the torque settings are for the cylinder head stud nuts, but when I put new studs in the block, is there a torque that I should be tightening them to?

Steve

[i.thomson]

No. It would be difficult anyway as double nuts or a stud remover are not really designed for that sort of thing. The locking effect on fasteners comes from the tension in the threads rather than the torque itself which is at best an inaccurate measure of this tension as it is complicated by the friction of the threads. They will, however, receive the same tensioning, and thus locking effect, as the top threads as the nuts are torqued. Just make sure that they go all the way into clean holes with good, chased threads to ensure the maximum thread length is engaged.
Ian Thomson

[Steve Simmons]

It's good practice to thread the stud all the way in, and then back off slightly. This ensures the stud is pulling, rather than pushing into the block. If the stud is all the way to the bottom and it turns slightly while tightening the nut, you can crack the block or reduce the gripping force of the threads. Ian is spot on!

[Tom Lange, MGT Repair]

I sell special ARP head studs, far superior to the originals or what is available today (Manley Ford and other racers use them with total confidence). My studs have two added features: an extra quarter inch of threads to accommodate heads that have been skimmed multiple times, and a hex in the upper end, for consistent installation.

I recommend torqueing my studs into the block to 10 foot-pounds, which can easily be measured with a hex driver on an inch-pound torque wrench. The techs at ARP recommend putting a drop of oil on the threads before installation (NOT in the threaded hole). At 120 inch/# torque the shoulder is snugged up against the deck of the block, but the threads do 95% of the contact.

Please see mgtrepair.net for a more complete description of these head studs and my ARP main studs.

Tom Lange
MGT Repair

[SteveW]

I was watching a Peter Edney engine rebuild DVD yesterday and he was recommending putting a little high temperature gasket compound on the stud threads that go into the block. Apparently sometimes there can be water leaks into the threaded bore that then rise up the threads by capillary action.

Any thoughts?

[Tom Lange, MGT Repair]

Don't see any reason why not, as I have heard of water leaks there. I've never had one, but there is always something new to be experienced! Compound would probably also act like a lubricant while tightening, so no thread oil would be necessary.

Tom Lange
MGT Repair