Rocker shims = NO rocker shaft oiling

Killer6,
If you set your pre-load to 020-025 & never popped a pushrod cup or circlip, it means........your springs were strong enough to contain 020-025 of pump up.
The rest I agree with.....
Cam manufacturers recommend springs that are strong enough to prevent lifter pump up for the upper rpm range of THAT cam for two reasons:
- pump up, even a small amount, causes a power loss because the valve is held open
- because pump up can knock out the p/rod cup, bend prods etc.