Re: Torque specs

Posted by PackardV8 On 2008/3/17 21:44:21

With the exception of some very modern applications nearly all castings Al or Iron that i have seen have COARSE threads, not fine threads wheather studs OR bolts are used. ONE EXCEPTION: my 48 Chief has 7/16-20 threads for head bolts into cast iron cylinders. If i remeber rite, the Packard V8 has COARSE thread 7/16 for head bolts.

Randy, i'm suprised u got away with 55 pounds of torque in the Al case without stripping. That's probably the limit.

In Al and with out specs, i would have pulled up the bolts with a 3/8 ratchet until they 'just stop' and then check it with a torque wrench and add 5 pounds over the highest reading. A good ball park guess is usually just fine when specs are not available. THE MAIN ISSUE is to have all of the bolts torqued to the SAME reading.