Recommended Viscosity Oil?
What is the idle rpm? Verified with a real gauge not just the dash? In an older smallblock with a stockish idle I would be OK, on an LS I have never paid that much attention or hooked up a mechanical gauge to one. That said the owner has to be comfortable. Also again one 5w-30 can be a fair bit thinner than another, and formulas change, M1 often tends to the thin end of ranges and Amsoil to the thick end.
Pressure is NOT what keeps the crank off the bearings, the crank basically hydroplanes.
Stop for a second and think about cranking compression psi times piston area times multiple cylinders. Then think about oil psi and bearing surface area. and now think about the cylinder pressure on the power stroke not the compression stroke we meaure.
Flow is what keeps the crank off the bearings.
We watch pressure because it lets us see deviations and is easily measured.
Pressure is NOT what keeps the crank off the bearings, the crank basically hydroplanes.
Stop for a second and think about cranking compression psi times piston area times multiple cylinders. Then think about oil psi and bearing surface area. and now think about the cylinder pressure on the power stroke not the compression stroke we meaure.
Flow is what keeps the crank off the bearings.
We watch pressure because it lets us see deviations and is easily measured.
What's the reasoning for the 40 weight oil in the summer and 30 weight oil in the winter? I can see the first number being different since most likey cold startup temps will vary greatly between the seasons. But as far as operating temps, regardless of whether it's 0* or 100* outside your oil temps will run basically the same (maybe a little higher in the summer).
Also in the winter it takes a lot longer to get to operating temperature if it ever does lol. I have a s10 blazer with a new 190 thermostat that can idle for a half hour and the temp will only reach 140-150 and not reach operating temperature until it's driven.
I will also add, If you have an separate oil cooler (2 of mine do)your oil will most definitely run cooler in the winter even when the engine is at the same temperature as it does in the summer.
I will also add, If you have an separate oil cooler (2 of mine do)your oil will most definitely run cooler in the winter even when the engine is at the same temperature as it does in the summer.
What oil do you use? There are plenty of pretty good 0w-40 or 5w40s if you're not dead set on a brand.
