JasonSmith

Ok, I'm changing out my factory stamped steel rockers to Comp Cams pro magnum rollers. I have the conversion studs & all the requires hardware for the install, but I have one question.
How will the hydraulic roller lifters affect the initial valve lash? Can the rockers be set cold? Should I prime them first by cranking the engines over a few times?
I'm working on a pair of 99 - 454 MPI MAGS (385 hp)
Thanks

Vinny P

I would make sure the lifters are pumped up. But cranking the engine over wont do it right. I like to pull the distributor and pump up the oil with an old cut up distibutor and drill. Those priming tools they sell dont work, you need an old distibutor to cut up. I can post a pisture if you need. Get the lifter on the cams base circle, pump it up before you adjust each rocker making sure you have oil at the lifter. Crank the adjuster in slowly while twisting the push rod with 2 fingers. When you feel the pushrod just stop turning, give the adjuster about 1/2 turn more.