Setting LT1 Valve Lash Cold
Race Director
Joined: May 2006
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You set them cold. Google 30-30 valve adjustment. There is a paper by John Hinckley and Duke Williams that covers the 30-30 and LT1 adjustment procedure. It requires you to adjust 2 valves at a time rotating the crankshaft by hand every 90 degrees for 2 rotations. Intake is .016 and exhaust is .023.
Dr. Detroit
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From: New Braunfels Texas
One thing I always wondered about the Hinckley paper is that he states that the service manual calls out for the valves to be set hot and running.......Ummm.....how exactly do you set solid lash running.....? Humor me please.
Jebby
Jebby
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Have 16 sets of disposable feeler gauges?
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Thanks Bob
Race Director
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Jebby, could you post the paper that you’re stating about John Hinckley, in reference to mechanical valves are set hot and running. I would like to past that the paper along too Duke Williams who is the other author of LT-1 mechanical valve adjustment paper with John Hinckley.
Thanks Bob
Thanks Bob
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I use the 2 valve lash at every 90* for all my solid lifter cams. I just use the manufacturers lash numbers. It works very well.
Team Owner
Joined: Jan 2006
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From: Crossville TN
Make sure that they are all a bit loose before you start the engine. As long as there is "some" clearance, there is no problem with setting them hot (as long as you have a way to deal with the oil splash).
Thread Starter
Drifting
Joined: May 2006
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From: Santa Barbara California
The 30-30 Cam and the LT1 cams are different and have different intake and exhaust clearances. The suggested method for setting the LT1 clearances is to do it warm. I would prefer to set them cold but wanted to know if there is a conversion in order to set them cold.
Race Director
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Download the paper it covers the LT1 cam and I gave you the cold settings in post 2 of this thread.