Used to drive my boat by the oil gauge. When the oil pressure started dropping, back off the throttle!One of the flaws is that the oil drain back holes in the heads are too small. At high rpms it can suck the pan dry but fill up the valve covers.
Used to drive my boat by the oil gauge. When the oil pressure started dropping, back off the throttle!One of the flaws is that the oil drain back holes in the heads are too small. At high rpms it can suck the pan dry but fill up the valve covers.
BTW, you are not quoting viscosity index, you are just quoting viscosity, the VI (Viscosity Index) is a calculated value based on the difference between the 100C and 40C viscosities.VR1 20w-50 Viscosity Index @ 212F = 20.5
Mobil1 15w-50 Viscosity Index @ 212F = 18.0
Redline 10w-60 Viscosity Index @ 212F = 25.9
With the above info. Would Redline 10w-60 give the highest oil pressure at a hot cruise?
BTW, you are not quoting viscosity index, you are just quoting viscosity, the VI (Viscosity Index) is a calculated value based on the difference between the 100C and 40C viscosities.
The number in front of the W is just the Winter grade of the oil, it's not the same as the number after the W, which is the "hot" grade, as measured at 100C. The oil is much, MUCH thicker when it's cold.How does Redline get such a vast viscosity swing from a 10 weight to a 60 weight?
Redline is likely using a significant amount of PAO in their base oil blend in order to achieve this, but they are also using VII's to pad the product up to the 25.9cSt hot viscosity.
Nope, not bad at all.Is that a "bad thing"? Can any harm come from that?
I only run the car in temps above 50F. So the cold start will never see anything below 50F.
You're right.I do not think his cam is on the small side for the type of driving the OP is doing.
Sometimes it's the "good old boys" too because that's what they remembered from "back in the day".Don't get hung up on oil pressure, higher is not better. The biggest mistake teenage/young street rodders who weren't educated on engine building dynamics would make is to order a 'high pressure' oil pump, a bigger mistake they would make is opt for the 'high volume' option pump from their local auto parts store. I saw quite a few oil starving situations upon tear-down due to 'high volume' pumps on a stock sized sump. You just watch for steady pressure, a sudden drop is indicative of an issue. But higher is not better.
The M1 15W-50 seems like a solid choice. Good luck
Run a girdle... less flex and then you can tighten up on those clearances.... I wonder if the fancy aluminum pans, when compared to stamped steel, can also help with block rigidity.I have an Olds 455 engine. These engines only had 2 bolt mains and a cast crank. They are low RPM torque monsters (shifting at 5,200 RPM but making 550 Ft Lbs of torque) but they suffered from weak cranks and weak main block webbing. The cranks and bottom end would "flex" under heavy loads and RPM and wipe out main and rod bearings. In order to avoid spinning & wiping a main bearing or rod bearing, extra main & rod bearing clearance has to be built into the rebuilds.
So typically an Olds 455 rebuild will see .003" on the rods and .004 - .0045" on the mains. This allows the engine to live but requires one to run a 50 weight oil. It's common for these engines to see oil pressures of 15-20psi hot idle and 45-50psi hot cruise (180F+ oil temps).
I noticed I get better hot oil pressure with the Valvoline VR1 20w-50 oil than I do with Mobil1 15w-50. I looked up the specs:
VR1 20w-50 Viscosity Index @ 212F = 20.5
Mobil1 15w-50 Viscosity Index @ 212F = 18.0
I am considering trying Redline 10w-60 which has a Viscosity Index @ 212F = 25.9
It has the highest VI at 212F out of all the oils I found. Pennzoil 10w-60 is close with a VI @ 212F = 23.2
I would estimate maybe a 5-10psi increase in hot oil pressure with the Redline 10w-60. Any pros/cons with running that oil?
He's pretty popular in my neck of the woods.Bill Trovato is the nations best Oldsmobile engine builder. http://www.btrperformance.com/about_us.html
He recommends the extra clearances to prevent wiping out the bearings. Only other way to tighten up the clearances is to run a forged or billet crank and to upgrade the 2-bolt mains with a girdle ($4,000 for parts and machining). With a forged crank and girdle, you can run tighter clearances but still not as tight as modern engines.
OMGThe Olds 455 has many flaws from the factory
I have the 7 quart oil pan and restricted cam bearings. That limits the amount of oil going to the upper end and keeps the oil down down in the mains and rods, where it is more needed.
It is also INTERNALLY balanced vs externally balanced (factory). The internal balance helps to prevent crank flex and stress. I am also running lightweight forged pistons and forged Eagle rods.
If you run the factory .0025" - .003 on the mains, at my power levels, you are guaranteed to wipe out the main bearings in a short while. The reality is the factory Olds 455 engine had a VERY short life. It would spin rod and main bearings within a few thousand miles if racing the engine. Most Olds 455's that were raced did not live long without wiping out a bearing.
The guys that race Olds 455's today, run the larger clearances and the engines live a long life, even if raced hard. Bill Trovato explains all this in his book: https://www.amazon.com/How-Build-Max-Performance-Oldsmobile-V-8s/dp/1613250738
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You’ve described a scenario that has been repeated too many times. These high volume-high pressure pumps by-pass oil straight back to the oil pan without being filtered. Might as well not run an oil filter. I eliminated the bypass on the last big block Chevy I built and used racing oil filters.Sometimes it's the "good old boys" too because that's what they remembered from "back in the day".
Not only that, but you are just wasting power thrashing the oil blasting it through the relief. Machine shop put an HV/HP pump ('m sure at his request) in a stock clearance'd SBC we were putting together for my buddy's dad and it had the stock SBC relief spring in it. Thing would make 80psi of oil pressure cold and be on the relief hot by like 2,500RPM, it was ridiculous, just wasting power and overwhelming the relief on the pump.
When we put together the roller motor a couple of years later we convinced him to go with a standard pump and things were where you wanted them to be. That engine is still going AFAIK, though he ripped off the Holley EFI setup and put a carb on it because he didn't like being unable to "tinker". Can't teach an old dog new tricks sometimes.
That’s an impressive block.The Big-Block Olds Lives On With Rocket Racing's Killer Casting
Rocket Racing and Performance has developed an aftermarket big-block Oldsmobile block that can handle all the horsepower you can make.www.enginelabs.com
Or run this block…