[MPKind]

I've been corresponding with Jack Rhoads about measuring for new push rods with the Rhoads V-PRO lifters. In an email he wrote, "Bottom out plunger when determining pushrod length and ADD about 0.020” to the pushrod." No explanation why you add it or what it does. I didn't really think anything of it until I started to really think about it. So I called him and got even more confused. He did mention that the V-PROs plunger travel is 50 - 60 thou. So I got more intrigued about why he wants to ADD 20 thou to the initial rod measurement. I've concluded that I really don't know so I sent him another email today with more questions.

If you have the rocker pinned in the sweet spot using mid-lift or the old witness mark method, why would you add another 20 thou and move the intake side of the rocker up more and not take into account rounding to the nearest 50 thou for the rod, or the additional bump you get when adjusting the lifters? I would think you 'd subtract some length, perhaps the plunger travel from low to high RPM so you can keep the rocker as close to mid-lift as possible when it's running at the higher RPMs...some constant that works with however you setup the lifter for you engine.

If you have any thoughts on this feel free to share.