The valvetrain of OHV/pushrod engines is heavy; you've got all the mass of big valves, the rocker arms, the pushrods, the lifters and the springs themselves. The valve and operating-end of the rocker contribute more to the inertial forces than the rest of the components, but all of them matter.
Valvetrain parts move. Moving mass = inertia. The spring must provide sufficient force to fully counteract the inertia of the valvetrain.
Using 4 little valves instead of 2 big ones decreases inertia. Using direct-acting bucket lifters instead of pushrods and rockers decreases inertia. The 2J lifters are simple and do not incorporate a hydraulic lash-adjusting feature - decreasing inertia.
Thus, an OHC bucket-style valvetrain requires a lot less spring than an OHV design.
I see no benefit to you to have the spring "pressure" (they say pressure, but they mean force) checked or equalized. However, Powerdynamix had damn well better set up your springs to the manufacturers specified installed height.
Valvetrain parts move. Moving mass = inertia. The spring must provide sufficient force to fully counteract the inertia of the valvetrain.
Using 4 little valves instead of 2 big ones decreases inertia. Using direct-acting bucket lifters instead of pushrods and rockers decreases inertia. The 2J lifters are simple and do not incorporate a hydraulic lash-adjusting feature - decreasing inertia.
Thus, an OHC bucket-style valvetrain requires a lot less spring than an OHV design.
I see no benefit to you to have the spring "pressure" (they say pressure, but they mean force) checked or equalized. However, Powerdynamix had damn well better set up your springs to the manufacturers specified installed height.
