Specific Oil Viscosity Question...

[Hal Copple]

i have over 70 thousand miles on the custom built 396 stroked Windsor in my SPF. I have run all sorts of oil viscosities, and have studied my oil pressures at standard (for me) conditions. I believe my engine too is "loose." But it neither burns nor leaks any oil. Here is what i eventually settled on for my hard-ridden motor. By the way, it runs the same even 180 psi of cylinder compression that it did when it was new.

I run the adjustable Melling high volume pump, with the set screw turned in all the way, about one more turn. I raised my oil sumps intake about a quarter inch more once when i had my pan off, which i have done about 5 times. It was really really close to the bottom of the pan, i think hindering oil pick-up a bit. Now, by the way, i use a marine Felpro silicone one-piece gasket, never a leak.

I used to run about 45-50 psi "hot" cruise, ie, 2000 rpm, oil at engine temp. If i uncovered my oil cooler, the oil temp did not increase on the gage, but i gained about 3-4 psi due to cooler (more viscous) oil in the engine. But my oil pressure did not rise much with increasing rpm.

So, i put on my car all AN 12 lines, including a Setrab oil cooler, and ran my oil return straight into the block at the adaptor, running my Accusump into thte motor via the old oil filter adaptor's oil inlet. Basically, i have more oil flow and pressure than i need now. So, i just changed back to 10-40, and hooked my cooler back up for the summer, i have some custom Goodridge oil lines i can swap out in about ten minutes. I can run my hot oil pressure up to well over 60 psi, but this is more oil flow than i need.

I have also spun off a distributor gear at 5000 rpm, but did not hurt the motor. I am on my fourth distributor gear, they do wear a bit. But much less now with my modifications, which cost me about $500 or more, and hours and hours of work to do. I have always run Red Line, but other oils are fine, too. I don't really believe it was necessary at all, just something for me to do for fun.

So, here is my suggestion: Oil pressure is related to oil flow volume, and oil flow resistance. I am aware of lots of Windsors than have many thousands of miles with about 45 psi hot, cruise, with nary a problem. Stroked Windsors seem to run a bit less PSI than the 351 displacement motors.

If you want that extra bit of security, put in the adjustable Melling high volume, but never rev your motor much unless you have good hot oil, and pull your distributor every 10K miles to check for wear. Mine is double-pinned to the Duraspark shaft. Turn the adjustor all the way in. Run the lightest weight synthic oil (after you are will broken in, i waited to about 4K miles), that gives you reasonable oil pressure. Don't worry much about hot idle oil pressure, a low load idling engine does not need much oil to keep it warm and happy. I run 10-40 winter, but last summer with the 20-50 Redline, i had more pressure than necessary, so i plan on keeping the 10-40 year around now. Your motor may like 20-50 in the heat of the summer. A functioning cooler will add a few pounds.

I now carry on long trips a spare alternator, ready to drop in, along with a spare alternator, tools and such. I think part of the longevity of my motor is that i baby it until it is good and warm.

Just my experience.