50 weight oil suggestion

[jetman]

Not much difference when it really gets hot

cSt viscosity at. 104F................212F.............at 302F

Straight 30............??.....................10.....................3
0W-20....................47 ..................8.8..................2.5
10W-30..................62 .................10....................3
0W-30....................57 ....................10..................3
5W-30..................59.....................10.....................3
10W-30................62.....................10....................3
0W-40..................85.....................15...................3.75
5W-50................120....................20....................4

 

[Vermess]

Not much difference when it really gets hot

cSt viscosity at. 104F................212F.............at 302F

Straight 30............??.....................10.....................3
0W-20....................47 ..................8.8..................2.5
10W-30..................62 .................10....................3
0W-30....................57 ....................10..................3
5W-30..................59.....................10.....................3
10W-30................62.....................10....................3
0W-40..................85.....................15...................3.75
5W-50................120....................20....................4

Thank you for this chart. This is why I recommended a oil cooler first and foremost.

 

[Vermess]

Thanks for the replies. The ecu is a holley dominator

Man, that sounds like a hot rod and a half. Checked out your pictures from this post a bit. Your hood.....great for engine cooling, great for getting heat away from those manifolds, horrible for the issue you are having. Couple that with the splitter, air comes in through the radiator, gets sucked out through the top, no air gets forced around the block or pan.

Not saying it's a bad design, it's actually really good for what you designed it for. It just has that one Achilles heel that can only be resolved with an oil cooler.

I have never put a car on the ax or road course without an oil cooler regardless of modifications.

 

[clinebarger]

I'm in agreement here, this sounds like cavitation and it's likely happening all along and just drops enough oil pressure to trip the system when the oil gets thin enough.

Oil pressure increases with RPM, typically until you hit the pump pressure relief, unless you are overwhelming the relief and then it goes beyond. A loss in oil pressure points to a supply problem to the pump.

Since this is an LSx topic, I'm going to tag @clinebarger so he can perhaps provide his expertise.

Anytime you're trying to move oil than what's physically possible...Cavitation will result.

LS engines with good clearances rarely NEED a High Volume/High Pressure oil pump, I shift my L92 at 6,200 with a stock LS6 oil pump with no issues, Though I would definitely need an oil cooler for any kind of road racing.

An issue I've ran across more than once.....Insufficient clearance between the Pick-up Tube Intake & the bottom of the Oil Pan, This will cause a restriction.

I'm curious as to what Oil Pan the OP is running? And the total Oil capacity?

For reference......A 6th gen LT1 powered Camaro SS holds 10 quarts of oil & has a oil cooler with a output of only 455HP. Trying to pump out 700HP with 5-6 quarts of oil & no cooler is a recipe some extreme oil temperatures.

 

[addyguy]

If it really is a problem with the oil getting too thin, and we are racing on warm sunny days, then a straight-weight seems to be the solution…’w’ numbers are pointless.

Redline racing SAE 50, Valvoline VR1 SAE 50 or 60, Kendall Nitro SAE 70, Amsoil motorcycle SAE 60 should all be considerations.