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http://members.tripod.com/torquespecs/hi_po_chev.htm


http://boxwrench.net/specs/chevy_sb.htm


if your useing aluminum heads don,t forget you need to use OILED steel washers under the bolt heads or on the studs under the nuts to get the correct torque readings
I normally run the bolt tq up in stages
55lbs
then re-torque in sequence to 60lbs
then re-torque in sequence to 65 lbs
BUT FOLLOW THE CYLINDER HEAD MANUFACTURERS ADVICE ON TQ SETTINGS AND REMEMBER TO DIP THE BOTTOM 3/4ths of the threads into permatex thread sealer
if its permatex thread sealer in white can with a dabber in the cap, looks like molasses with a black color /slightly redish tint on white paper your useing the correct sealer




the can says" super 300" and part # 80057 on it! just dip your clean dry studs threads or bolt threads 3/4 of the thread length in the can, and let it stop dripping then install the stud in a clean dry threaded hole, don,t add coolent to the block for at least 3-4 hours , I can,t even remember the last thread/stud that leaked useing that method
 

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Your torque spec's for aluminum heads are WRONG.

Most alum. head's start at a very low tq. 30-35 ft.lb. then work up some require a wait period of up to 20 min. between retorque then a release of all bolts,then tighten then down to the final tq. and that depends on if you have studs or bolts, but in all cases the final tq. will be over 65 lb. with aluminum.

Make sure you use a soft head gasket too. You don't want to indent the heads!
 

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I think I saw this in that post:

grumpyvette said:

BUT FOLLOW THE CYLINDER HEAD MANUFACTURERS ADVICE ON TQ SETTINGS
[/B]
Here is AFR's recommendation:

7) HEAD BOLT TORQUE:
All Aluminum heads should be torqued to 65-70 ft/lbs. This should
be done in the proper General Motors sequence in 10 ft/lbs increments beginning at 40 ft/lbs. Moly lube should be applied between fasteners, washers and areas around head bolt to prevent galling and improper torque values. All high compression, supercharged, turbocharged & nitrous motors should receive a retorque after the first run-in and complete cool down. Bolts containing a 12 point head are suggested in 3 areas on each head near the exhaust valve springs where it may be difficult to fit a standard 5/8 hex head socket. In case of head studs, use 12 point nuts. Airflow Research stocks complete and partial head bolt kits, studs and washers for your convenience. Proper ARP #'s for head bolt kit use #134-3701 and head stud kit use #234-4301. Sealer should be applied to all threaded areas that enter into the block water jacketing, Permatex is a good general purpose sealer.
 

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Good info, thanks. :)
 
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