Help on LT1 head torque..PLEASE!!!!!
Thread Starter
Safety Car
Joined: Aug 2006
Posts: 4,102
Likes: 1
From: Forsyth Illinois
Help on LT1 head torque..PLEASE!!!!!
I am build ing a 69 vert w/a 93 Lt1/700r4 trans.The engine was a very low mile police car wreck,and I got aluminum heads,etc.from a 94.My question is.......A friend of mine works at a Chevy dealer,and said that i was suppose to torque the aluminum heads w/a degree torque wrench,rather than the foot/lbs.torque wrench.Could anyone here,PLEASE tell me the correct torque?All my cars are 75 vbettes,and older,so the LT1 is a new creature to me,and I have no room for errors.Thanks in advance!
Race Director
Joined: Apr 2000
Posts: 15,344
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From: Texas
If you use factory LT1 bolts your friend is correct. They are one time use "torque to yield". With those bolts you torque them to a defined setting and then tighten them an additional "x" degrees. This is in the factory service manual. If you reuse the factory bolts you risk breaking them (or having them break while the engine is running) since they are stretched when tightened.
Most likely what you'll want to do (unless you want to buy the tool to use OEM bolts), is buy a nice set of ARP headbolts. Those are torqued in the traditional manner to 65 ft lbs.
Most likely what you'll want to do (unless you want to buy the tool to use OEM bolts), is buy a nice set of ARP headbolts. Those are torqued in the traditional manner to 65 ft lbs.
Instructor
Joined: Apr 2007
Posts: 127
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I assumed that you were using new aftermarket bolts. The strech bolts are use once , just like he said, and the aftermarket bolts should be . You should re-torque after the first tuning runs and a few miles after. 500 or so.
