If there is a difference between how the engine runs [ smooth or rough, post #13 ], it means the lash is different between both methods.
I suspect with an all iron engine, there will be little or no difference between the hot/cold setting.
suposedly .004 on a cast iron head, .006 on an aluminum head= cold
I have been setting my solid roller cam/alum. heads at .006 tighter for 12ish yrs. , the one time I checked them they were right on , have had no problems ...
