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Old 28th December 2007, 01:48 PM   #4 (permalink)
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jac mac
I Have No Life
New Zealand
 
Join Date: Dec 2005
Location: Gore, NZ
Posts: 3,221
Re: Engine assembly question

Around 4 ft lbs per liter for the Block assy (eg: 302ci/5000cc = 20 ft lb ) for race engine, some higher tension ring packs etc on normal motors up to 8 ft lb per liter. The Bore/Stroke is factor in this also older rope rear seal etc add more still.

Bare crank only with all mains torqued- around 1ft lb ( you should be able to twist it by hand on the crank snout/damper area quite freely with no real resistance - No rear seal fitted ). A length of cord wrapped around the front pulley with a known weight for the pulley dia will give you a torque figure in this scenario.

Once the valve train is installed all bets are off due to spring rates etc, It pays to pre install valve train one step at a time in radical setups to check for interference etc. Some stroker applications MUST have the cam timed before turning the assy over in order to prevent the crank/rod assy from contacting the lobes- if a timing chain ever breaks on one of those babies there is a lot of mech mayhem in a short time frame.

Last edited by jac mac; 28th December 2007 at 01:52 PM. Reason: xtra
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