Re: What size oil cooler do I need ?
 

Blue Thunder explained my thoughts on oil temp sender location better than I did.

I believe the center valve is needed only when an automotive type cooler is plumbed in to the block, in the two threaded holes which are located just in front of the filter pad on the block. In a marine application when a remote oil pad and oil cooler are used, the center valve creates a restriction. cfm has posted a quote from GM on the subject. Check with him and see if he will post it again, or try a search. The GM quote gives a pretty good explanation.

Re: What size oil cooler do I need ?
 

The bypass is actually a pressure differential valve. The poppet of the valve has pressure on both sides of it. One side is pressure from the oil pump, the other is pressure coming back after the oil went through the cooler and filter. If the pressure returning from the filter and coolers drops due to blockage, the pressure on the underside of the poppet drops and the poppet opens. This allows flow past the cooler and filter but back into the normal lub circuit towards the mains.

That is if we are talking about the same bypass valve...

BT :cool:

Re: What size oil cooler do I need ?
 

Im glad Ive got mark 4's. Reading that gave me a headache.

Re: What size oil cooler do I need ?
 

I gotta believe that in Teagueland the sun rises in the West. Where I live, (and until someone can give me a GOOD reason why I should not) I will be cooling my oil AFTER I filter it and measuring the temp. at the filter pad where it comes from the pan, compressed, and is probably at max temps. (other than directly at the load surfaces). --- Jer

Re: What size oil cooler do I need ?
 

Ditto,

now, is 260 before the cooler at wot acceptable or not.

Re: What size oil cooler do I need ?
 

Now you are asking a real non-expert. I'll start by saying that I would listen to whatever cstraub says. Then I would say that I guess I wouldn't worry if I occasionally peaked at as much as 270* right out of the pan as long as that is the "occasional peak" and not the normal run temp., and I was running a good full synthetic oil. See, I avoided giving you a direct answer just like everybody else here. --- Jer

Re: What size oil cooler do I need ?
 

I may not have seen a roller lifter develop a flat spot but I did see a roller rocker develop this with the use of 15w-50 MobilOne.
It came out of a HP525SC.
My engine builder also races in some Cat class...he uses a straight weight Kendal GT1 also....but recomends 20w-50 for pleasure use.

Applications
GT-1™ High Performance Motor Oil is recommended for use in
passenger cars, vans, light trucks and sports utility vehicles
under all driving conditions, as well as in competition engines
and high-performance street engines. The SAE 20W-50 and 50
viscosity grades are fortified to provide extra wear protection
and foam resistance for use in racing applications. The SAE 70
viscosity grade is specially formulated for use in nitromethanefueled
drag racing vehicles. The SAE 30 and 40 viscosity
grades are suitable for use in older vehicles where use of a single
grade motor oil is recommended.

Re: What size oil cooler do I need ?
 

Well, as funky as it sounds, im gonna add my old 7.4 coolers to the vertical water hose coming up the front of the block, theres room and it doesnt create other mounting issues like a bigger cooler will. Then toss the aluminum pans and go back to the 8 quart sheet metal ones. Least amount of hit money wise and should give me the 20 degrees I need.