valve settings

I have read on here about reducing the valve settings when using aluminum heads.  I have P51' heads and a comp solid roller that calls for .018/.019 settings.  What should I set them for on a cold engine?  Its a never fired 545

If it's a hot lash I would set them cold .015/.016 then check them hot and see where it is

Aluminum heads, if the hot lash is .016" and that's where you want it, cold lash is going to be about .026" every head is different, but your going to get somewhere between .008" to .015" growth with the aluminum heads being hot.

Iron block with aluminum heads you subtract from hot lash DO NOT ADD lash for a cold setting

Set them cold, to your hot lash setting.  Start engine and build heat.  Set 1 side, button up. Reheat, set other side.  Check cold lash value after your proper hot lash setting.

Set them cold, to your hot lash setting.  Start engine and build heat.  Set 1 side, button up. Reheat, set other side.  Check cold lash value after your proper hot lash setting.  That tells you how much your heads grow when hot, and what  the minimum lash adjustment you can go to.
 And yes, ss pointed out above, my first information was head up ass moment.  Too tight hot, can hsve valve off seat cold.  Cold lash is that .008 to .010 less than hot.

Larry Williams wrote:I have read on here about reducing the valve settings when using aluminum heads.  I have P51' heads and a comp solid roller that calls for .018/.019 settings.  What should I set them for on a cold engine?  Its a never fired 545

I would set them about .004" tighter when cold with aluminum heads.

rmcomprandy wrote:

Larry Williams wrote:I have read on here about reducing the valve settings when using aluminum heads.  I have P51' heads and a comp solid roller that calls for .018/.019 settings.  What should I set them for on a cold engine?  Its a never fired 545

I would set them about .004" tighter when cold with aluminum heads.

Randy is my hero.
.004" tighter is usually pretty close.
Keith

just the answers I needed thank you all who replied .004 it is