I'd trust ARP on that! A stud has threads on both ends. Torque, although
achieved by twisting, is in this context a measure of how much the threaded
item is stretched. Torque a stud and you are stretching it against both the
head threads and the nut threads at the same time. Torque the stud into the
block (or wherever) first, and it then already has some measure of stretch
on it so torquing it from the nut would seem to have different measures of
torque in the block end than on the nut end. Besides, usually the block (or
wherever) end has a lot more threads engaged than the nut end. Just spin
them into the block until they won't go any deeper. If they don't seem to go
deep enough, you may need to clean out the hole. Try it first dry, not with
the sealant, to make sure they go as deep as you want them to, then take it
out, put the sealant on, and put them in for keeps.
Besides it is a real PITA to torque something that has no head. You have to
use two nuts jammed together, and then you are torquing them against each
other and partly "using up" the nut end of the stud for no good reason.
Old trick when I was still using the stock head studs -- used lugnuts for
the head nuts as they were the same thread. It meant more threads were
engaged at the nut end and less chance of stripping a nut or a stud. More
recently, my engine builder built the block with oversize studs, and then
tells me to torque some 20# over standard (and do it hot).
--Rocky Entriken
----- Original Message -----
From: "Brad Eells" <bradlnss@lightspeed.net>
To: <FOT@autox.team.net>
Sent: Tuesday, March 02, 2004 7:32 PM
Subject: RE: re-torqing cylinder heads hot???
> As long as we're on the question...head studs...when I purchased my set
from
> ARP, their instructions were to thread the studs into the block (with
their
> special thread sealant) only hand tight.
>
> Do those of you with great engine building experience agree or do you
> tighten them into the block in some additional way? Describe your process.
>
> Thanks,
>
> Brad
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