I've always done it with engine off and cold.
Turn dampner with big wrench until No. 1 exhaust valve rocker 'just starts to open'.......no.1 intake should be all the way on the heel (bottom of lobe) of cam. Fully closed. Turn the adjusting nut on intake rocker while 'twirling/spinning' the pushrod between your fingers.When you feel the push rod stop spinning STOP!   Give the adjusting nut 1/2 turn. Then go to the exhaust valve and rotate the dampner until it is on the heel of the cam lobe............and repeat steps all the way around.
6sal6

Last edited by 6sally6 (2/13/2020 10:26 PM)

I've done them both ways over the years.  If running, the method I learned from an old school mechanic was to loosen them one at a time until they tick, tighten them until the tick goes away, then go another 1/4 turn.  He said most hydraulic cam cars were at least 1 full turn too tight from the factory and it caused soggy performance. 

When setting them up cold I would put the cam on the base circle for the valve being adjusted, then adjust until I had zero slack as felt by moving the pushrod up and down.  I've heard of twisting them until resistance was felt but never had any luck doing it that way; they always ended up too tight.  Once at zero clearance go 1/4-1/2 turn past zero to set lifter preload.