They are both fast ramp cams, so why would one be noisy for some people and not for others? The Comp Cams and lifters I took out look great, no ware at all but I wouldn't even give it to someone because I would want to piss them off. Shitty grinds from two different companies? Maybe someone got fired at one place and got hired at the other.
Oil weight and type has an effect too. I have found that the thinner actual viscosities of synthetics at even room temp makes lifters noisy when cool. And different weights of the same type can have an effect.
I also wonder about the exact lifter employed in these cases.. regular or anti-pump up can make a difference.
