oil suspension issues

The 351C oil drain-back passages from the heads to the oil pan are small, sustained high RPM will result in all of the oil collecting in the rocker covers & starving the oil pump.

External drain lines between both ends of each head (4 total) and the oil pan must be manufactured:









The oil restrictors to the cam bearings are one part of controlling where the oil goes. The best way to restrict oil flow to the top end is via the installation of bronze bushings in each lifter bore (all 16 of them), with a small restricted hole supplying oil to each lifter, the bushings should also be fitted to the lifters with a small 0.0007" clearance. Not only does this limit oil flow to the top end, it also ensures oil is supplied to the crank, and not leaking past the lifters, it prevents oil from collecting in the lifter valley, dripping down on the crankshaft and becoming aerated. Restricting oil to the top end makes roller rocker arms like those you have already installed a necessity because they require less oil for lubrication. If you're going to twist the motor above 7000 rpm that will call for fully grooved main bearings to help the rod bearings survive.

Aeration of the oil will be a major concern in your application, your oil pan needs a windage tray & scraper, and your crankcase should have a small vacuum on it to pull as much air as possible out of the oil. Caution here however, because the wet sump oil pump will not pull the oil out of the pan if the vacuum in the crankcase is too great. You would be better off with a dry sump system.

If you plan to run a wet sump oil system, a standard capacity oil pump is sufficient, but it should be fitted with a high pressure relief spring. When using the high pressure relief spring you need the insurance of an oil filter designed for high pressure such as the Fram HP1. Oil temperature will also be a concern at high speeds, so you may want to consider an air to oil cooler. If you install the cooler the higher volume oil pump would be called for.

Fill the oil pan with Amsoil 20W50 and rock 'n' roll.

Cowboy
great stuff, I was planning to install external oil returns for the heads but the rear only, figuring the cam chain and dist. gear would need the oil. my 10 qt pan has a windage tray or splash tray with traps but not close to the crank. what are full grove main brgs? two top halfs? .0007 on the lifter bore seems very tight. I have a small oil cooler, not sure if i want to run it. 10" long U shape. mabe not big enough. What do you think about an oil accumulator, 3 Qt or so. High press sping in a standard oil pump. How do i order this? Do you have any pics of the oil returns back into the pan.
Larry

Cowboy, one more thing. the original oil return passage (cyl head) does it get plugged or left open thanks Larry

quote:

Originally posted by tyler5:
I was planning to install external oil returns for the heads but the rear only,
No, add drains to both ends, because you have to stop the car at some point, and stopping from 200 MPH means the G Force during deceleration will pack the oil forward in the valve covers

what are full grove main brgs? two top halfs?
Both halves are grooved. Clevite 77 #MS1010VG, provides oil to the con rods over 360 degrees of crankshaft rotation

.0007 on the lifter bore seems very tight.
0.0007 is Ford's minimum spec for that clearance, right out of the factory repair manual. Think of the clearance this way ... 0.001 +/- 0.0003. The idea is to keep that clearance about 1/2 of the clearance for the main bearings or the rods, the oil shall flow to the path of least resistance

I have a small oil cooler, not sure if i want to run it. 10" long U shape. mabe not big enough.
You shall need an oil cooler, I prefer an air to oil type cooler with a thermostat, mount it in a box on the left hand side of the engine compartment and duct cool air to it

What do you think about an oil accumulator, 3 Qt or so.
I think its a good idea

High press sping in a standard oil pump. How do i order this?
Moroso #22850

Do you have any pics of the oil returns back into the pan.
No, sorry. Use bulk head fittings or weld NPT bungs on the pan, mount them to dump into the sump below the oil level

quote:

Originally posted by tyler5:
the original oil return passage (cyl head) does it get plugged or left open
Left Open

George
thanks, your a cleveland guru. Larry