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a newly assembled 351, do a cold valve adjustment, fire up, break in,at operating temp. bring motor to idle, and do a hot valve adjustment. new school says after the break in , run motor for a half hour or to operating temp.shut motor off and adj. hot valve adjustment. [no hot oil all over the place, and you get the same adj. as if it was running.] whats up??? thanks
 

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Hmmmmmm.......valve lash on my cam is .025" cold, intake and exhaust. I just set it cold and let it go. Is this the right way to do it? I dunno, but that's what Scott Main told me to do
 

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I always set them cold. Then warm the engine up, and shut it down. Go back and check the lash. Much cleaner.
 

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Same here, set it cold and forget about it once broken in. Lash won't change if using poly locks and stud guirdles with heavy springs and a solid cam. I also have always run tighter lash than the cam cards call for. Less noise and more power at operating temp.
 

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Discussion Starter #6
thank you guys, correct me if iam wrong, kent and sandman, but i been told theres a huge differance,between a cold adj.and a hot adj.mainly the valves opening to soon or closeing to late, and robbing power,plus early wear an tear on the cam??? your opinion is valued. thanks
 

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You can make the cam seem "bigger" by tightening up the lash, say going from .025" lash to .020"-.022". Correct me fellas if I'm wrong, but I think tightening the lash gives more bottom end, and loosening it up gives more top end. You don't want to go too tight when adjusting cold, as when the engine warms up things tighten up a few thou.

Hope this helps a little
 

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I did my adj a couple of times hot and then checked to see what it was once it got cold, Now I adj it while its cold with the new size.
 

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hear is what crane cam says to do, with a cold engine with iron block and iron heads add .002" with iron block and aluminum heads subtract .006" with all aluminum heads and block subtract .012" it worked for me iron and iron when the engine got hot the spec came out just right to the cam card

Alan
 
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