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Super Moderator
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Discussion Starter #1 (Edited)
THE HEAD BOLTS REQUIRE the use of THREAD SEALANT ALSO




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
On small blocks 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

youll normally be just fine runing the bolts in to the specific torque settings in stages then waiting a few minutes and going back over them again to make double sure you got them all correctly torqued, many guys recheck the headbolt torque settings & retorque the heads after the cam break-in after the engine cools the first time but thats normally not necessary the first and sometimes MOST important 10% of any job worth doing is making 100% sure you know the correct way to do something and that you havre the correct tools and parts with detailed instructions, yes you can memorize the correct info but if you need the correct sbc TQ values as an example
http://www.torquespecs.com/

http://www.2quicknovas.com/torque.html


http://www.cobra-replica.co.uk/html/cobra_54.shtml

http://rodshack.port5.com/t_torque_big_block.htm

http://www.darklair.com/monte/torque_specs.html

http://www.gearheadracing.com/Reference/TorqueSpecChevy.htm

http://www.summitracing.com/tech/charts_guides/tz_02cht_gds_mprtrq_p.htm

http://www.hotrodshack.com/torque_settings.htm


its alot easier if youve got referances in your data base
 

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resident conservative
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If I can add to this, one of the things I have learned on working on diesels is to "hold the torque " on the head bolt for a 5 sec count to equalize the force on the bolt.
 

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Super Moderator
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Discussion Starter #4
if several retorque stages is what the manufacturer suggests theres a reason, they suggest it, manufacturers don,t just stick silly info in to make you nuts. now Ive always gradually snuck up my cylinder head bolt torque up in stages then I go back several times retorqueing the bolts at the max setting, to allow the bolts to take a set, and have never had the slightest problem, but I have noticed that on some occasions the second retorque has some bolts turn further in slightly as the bolts settle in to max torque,(its very important to use the thread sealer and oil the bolt heads and washers to get consistant readings, and a CALIBRATED,click type torque wrench not the swinging pointer style is vastly prefered) you will not damage the head gasket by torqueing and retourqueing the heads as long as you never remove the heads during the process, dropping the torque setting on the bolts and then retorqueing the bolts back to max torque at the time of installation, hurts nothing as long as its done in the center out spiral pattern chevy suggests and will only help the gasket more firmly settle into place. that center out spiral pattern is designed to allow the head to stretch evenly,so keep that in mind.

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