The pump can only move so much oil at a given RPM. The relief valve shouldn't even be in mix at idle speed. Low pressure at idle is due to internal bleed. In my testing the bearing clearance doesn't affect it much. Oil feed to the top seems to be a more promenent factor. My engine runs .003" rod, .004" main, .0025" lifter bore clearance. This engine with a .095" pushrod orifice would only make 45psi@7000 vs 90psi@7000 with a .055" pushrod orifice (same relief spring and clearance's).
Are you talking about restricting oil up to the rockers with the .055 orifice?
I pushrod oil so each pushrod is restricted to .055". This is still a TON of oil. I know plenty that restrict Indy feed lines to .040". And thats 2 vs 16 feeds.
You must be lubing roller rockers? There is now known reason for pushrod lubricated stock valve trains.
The valvetrain is altered. All oil to the valvetrain is fed thru the pushrods. Bushed lifter bores,.100" orifice. Push rod 7/16"x.165" wall tapered pushrod, 1.7 T&D paired rocker shaft system. The four shafts bolt to a bed plate on each head. All oil is fed thru the lifter bushing> roller tappet>pushrod>lash adjuster>rocker>rocker needle bearing.
Do the rockers oil directly by passage from push rod oil or is this a pee and drip system such as found in older GM's?
Direct feed from the pushrod only.
So it lubes the rollers in the rocker from splash of the valve cover.
Nope, the adjuster has a hole through the center and a machined undercut in the thread. There is a passage through the rocker to the roller bearing. One more passage underneath that squirts at the roller tip. T&D makes a nice product. I run 320/800 spring. A friend runs 400+/1000+. Never a body failure. I did replace the needle bearings and a couple of shafts after 350 passes. I had never inspected them after purchasing them used from a guy who had many years on them. Bearings were only $3 from T&D, shafts $24 very reasonable.
