We've learned that weight on the lifter side of the ocker is far less a concern than system rigidity. The last thing you need in a pushrod valve train is another spring in the system which is essentially what a "weak" pushrod becomes. I would never put a performance FE back together with the stock dia. pushrods. It's pretty hard to run "too big" of a pushrod and cross sectional diameter always trumps wall thickness. Look at the cup guys running way more lift than anything discussed here at 9000rpm for 500 mi...with 80# seat pressure. Yes, their stuff is developed on a spintron but none the less..."intuitively" throwing more spring pressure at a system is not always the best solution. They have .500"+ dia. pushrods with that 80# seat pressure. And they're short. VERY rigid.
One other thing to consider...I keep hearing comments about the spring pressure needed with a solid roller, yet with a hyd. roller's much heavier lifter, we get away with less spring pressure. It's the lobe that dictates the spring pressure, so if you have a very mild solid roller...something comparable to a hyd roller only with a lash ramp, then the spring pressures don't need to be anything unreasonable (for those of you who are adverse to a hyd roller, but willing to go solid). Finally, don't be afraid of a little spring pressure. While yes, you can usually get away with less, this is an area where a little more is not a bad thing. It's way better to have more than enough, than less than enough. Weak springs is the kiss of death in any valve train, especially a pushrod design. Sprig pressure is what keeps things under control, and it's when we lose control is when all the damage and breaking takes place.
Just some of my thoughts on the subject.
