Should this be done differently that with cast iron heads? My thought is as the aluminum expands the rocker arm is now higher than before, which effectively loosens the "lash", for lack of a more correct term.

The reason I ask this is because when I am first driving my car and it is not up to temp, the engine is very quiet. At temperature, there is a lot of clatter, from what I believe is due to a gap between the top of the valve and the roller rocker. Also, I set the valves when the motor was cold, to zero lash and 3/4 turn. lifters are retrofit hyd rollers if it makes a difference. Should I be using more preload when setting them cold?

Not sure about hydraulic lifters but I set my solid rollers .004" wider when cold since aluminum expands more than iron.

Not sure about hydraulic lifters but I set my solid rollers .004" wider when cold since aluminum expands more than iron.
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Hyd lifters:
Unless you are setting them at zero you don't need to change anything cold to hot.
Yours will change .004 which is less than an eighth turn
An eighth turn is .00625 in case you were wondering ;)

Solid lifters
Aluminum heads, iron block
BB .006 tighter cold not looser.
SB .004 tighter

Hmm so I wonder why I get so much chatter when it is warm? Should I try more pre-load or could my pushrods possibly be a little too short?

Your oil is probably thicker when the engine is cold. That may quiet normal noise some.

BBC aluminum heads...solid roller...I always lash .006" tighter then what is called for on the cam card when doing them cold.
Works out perfect! :thumbsup:

I set mine the same way...006 tight when cold.

When I go to the track..I usually pull to the line with engine relatively cold. I run it long enough to heat up oil some and try to end up with hot oil/cold water.

I've found that after a full pass and then idling back to the pits..they will open up about .003 maybe. They only open up the full .006 if I'm on the street cruising and really get some heat in it. Like a 2 hour drive on highway or cruising around all night.

I still set them tight....I don't like hearing it beating itself to death.


JIM