High volume oil pump 98 K1500 5.7

[Road Trip]

And folks in my racing class have pretty much abandoned accumulators. Presumably they are to blame for a number of engine failures. I believe charging the thing mid corner was starving the engines. Not sure, I get by with my stock oil pan and short SBC style pickup.

With the ever-improved handling/increasing lateral G forces over time, trying to
deliver non-stop oil pressure from a wet-sump setup is increasingly difficult/futile.

One concern about recharging the accumulator would be that now the oil pump is
being asked to service 2 masters simultaneously. (Engine + accumulator) To me,
this is one scenario where a high volume oil pump is definitely the way to go. Saying it
another way, putting all the time & effort into an Accusump setup with a stock oil pump...
and then having the 'new & improved' setup fail to deliver would s*ck, plain & simple.

Also, while reading your post I thought of me out on the track, overly focused on the
almighty mechanical oil pressure gauge -- meanwhile, all my competitors are whizzing
by me on the track. I consider myself pretty competitive, but I'm afraid I'd have to tape
over the oil pressure gauge if I was serious about actually winning the race.

Seriously, this would be a perfect case to justify oil pressure telemetry which could be reviewed
after the race to see if/where the problem spots are on the track & make the necessary
changes.

Then again, (if the racing rules allow) the dry sump guys would be laughing at my attempts
to (try to) deliver enough steady oil pressure to finish the race. (new Corvette dry sump setup.)

When it comes to wet sump oiling systems, the phrase "Out of Sight, Out of Mind" applies.
Anyone who has ever had an open cup of hot coffee in their truck knows exactly what I'm
talking about the first time they take a 90° turn at anything over, say, 10mph.

In English, what makes perfect sense in the engine oil pan during a stationary dyno run turns
into pure liquid chaos when road racing at full tilt. (!) Honestly, sometimes I don't believe this
stuff has any chance of working at all. :0)

...Even so, my beating heart still yearns for an Accusump for the chore truck. Can't seem to get
over the allure of wet-starting the powerplant. Such a great oil delivery system that I could quit
studying all this tribology nonsense & just enjoy the ride. :0)

 

[0xDEADBEEF]

BTW, in my experience what kills motors is long turns. The carousel at COTA is ~1.1g for ~9 seconds give or take at maintenance throttle in my C8 (dry sump). I put oil pan baffles in my C5 but I don't know if they really helped. I heard engine ticking in that turn a lot if I drove the proper line.

 

[Supercharged111]

BTW, in my experience what kills motors is long turns. The carousel at COTA is ~1.1g for ~9 seconds give or take at maintenance throttle in my C8 (dry sump). I put oil pan baffles in my C5 but I don't know if they really helped. I heard engine ticking in that turn a lot if I drove the proper line.

Ya know what's wild? We have had zero issues running at PPIR which is a roval. While not a super fun track, holy crap that banking! There's really something to be said about hauling ass that close to a cement wall, you have to play chicken with it essentially. And the sound of the car when you get right next to it is so badass.

 

[Supercharged111]

The SAE Hi-Temp specification has stayed clear & unambiguous for a long time -- it really is 100°C. (212°F)

Interestingly, it's possible to overcool engine oil -- it's generally agreed that (especially for street-driven vehicles)
the best engine oil temp is just over the boiling point of water, so that when the engine is up to temp the
blow-by contaminants (water vapor) are boiled out of the lubricant & removed by the PCV subsystem...instead
of having this moisture hanging around in the crankcase and helping to turn engine oil into sludge. (!)

In English, the trucks that came equipped with engine oil 'coolers' benefit the engine's lifeblood during both
extreme southern heat as well as northern US/Canada shorter-trip cold weather operation. (!)

****

On the other hand, when it comes to low temp testing the SAE specs get a bit confusing, especially given
the fact that SAE has changed up the low temp (W rating) over the years. But I think I've got a
handle on all this. (NOTE: The following is optional reading for normal folks. Amateur tribologist? Check it out: )

=========================================================================

1) While unknowingly referencing old SAE documents:

For example, when I was reading about the difference between specs for a 20W vs. a straight weight "20" oil,
it turns out that the straight 20 weight oil is spec'd at 40°C (104°F) & 100°C. (212°F)

Meanwhile, 20W oil is indeed spec'd at 0°F. (-17°C):

You must be registered for see images attach

The 'W' denotes a different (cold oriented) testing strategy. 20W is rated at a different temp than straight 20. (!)

2) Referencing the new 2015 SAE document for winter & non-winter engine oil grades: (J300)

OK, so after locating excerpts from SAE's J300 doc & giving it a read, I now understand where a lot of the
confusion surrounding engine oil low-temp specs have come from.

First of all, years ago the 'W' rating indicated that this oil was tested at 0° Fahrenheit. Now, according
to the 2015 document, the cold temp ratings are now made in °Centigrade. Furthermore, the actual resistance
to flow is now held as a constant, and actual "temp to W rating' is on a sliding temperature scale?

Here's an excerpt that actually makes this pretty clear:

NOTE: I've added the matching Fahrenheit numbers for those of us who grew up with this stuff.

You must be registered for see images attach

(credit: Wiki link)

Given all of the above, when the SAE moved the low-temp testing goalposts for the W(inter) rating, it created
some confusion regarding 0°F vs. 0°C. And now the sliding temp scale?

Another thing about the oil ratings is that there is an increasing overlap between
Winter (0W, 5W, 10W, 15W, 20W, & 25W) rated oils vs. the
non-winter 100° C rated (8, 12, 16, 20, 30, 40, 50, & 60) oils. SAE tried to
minimize the confusion by incrementing the new weights by 4 to help avoid
end-customer confusion. I don't know -- it seems that regular folks have
a lot of questions surrounding all this. I know I do. :0)

If anything, I still have confidence in the oil viscosity chart in the '99 C/K Service Manual.

Here's hoping we're all on the same (SAE) page now.

I think I read the 0 and 100 thing on Bob is the oil guy eons ago, but this is hands down better information with supporting info.

 

[Erik the Awful]

Engine Masters had a pretty good episode recently (S8E13) where they tested different weights of oil to see how much power they robbed. Counter-intuitively, 20w50 didn't rob horsepower. Got low oil pressure? I'd step up to 20w50 and start an engine build on the side.

We don't run an accusump. We can't afford it and don't need it. If you want a poor man's accusump, take a fire extinguisher bottle, remove the top, and weld a fitting into the outlet. Mount it with the fitting down. If you want you can prefill it with a few ounces of oil. Put a ball valve on it with a cable to the dash. Hook up your oil cooler lines to it. The air trapped inside will compress when the engine's running. Close that valve before shutdown and you'll have your pressurized oil for pre-lubing. The only advantage of an actual accusump is that you can mount it sideways.

 

[Road Trip]

We don't run an accusump. We can't afford it and don't need it. If you want a poor man's accusump, take a fire extinguisher bottle, remove the top, and weld a fitting into the outlet. Mount it with the fitting down. If you want you can prefill it with a few ounces of oil. Put a ball valve on it with a cable to the dash. Hook up your oil cooler lines to it. The air trapped inside will compress when the engine's running. Close that valve before shutdown and you'll have your pressurized oil for pre-lubing. The only advantage of an actual accusump is that you can mount it sideways.

What a great suggestion -- Intriguing yet affordable!

I appreciate the food for thought.

Very cool. Thanks!

 

[L31MaxExpress]

I really do not see a need to prelube before starting. I pulled an engine apart a while back that had sat for nearly a decade. All the internal parts still had a nice film of oil present. The oil pump will be spinning before the engine fires. Most GM vehicles have the cranking fuel pulse delayed some number of reference pulses before the PCM pulses the injectors too.

Remember those Slick50 demonstrator engines they ran without an oil pan? Plenty of oil film left to run the minimal amount of time needed.

 

[Pinger]

I really do not see a need to prelube before starting. I pulled an engine apart a while back that had sat for nearly a decade. All the internal parts still had a nice film of oil present. The oil pump will be spinning before the engine fires. Most GM vehicles have the cranking fuel pulse delayed some number of reference pulses before the PCM pulses the injectors too.

I can - and sometimes do in winter - expand on that. I have a switch on the dash to switch off the fuel pump when I'm running on LPG (propane). Cranking the engine for a bit before enabling the pump helps get the oil moving before the engine fires. Can't say it makes any difference or that I'm overly zealous with my cold start regime but I have the option to push some oil before the firing begins.

 

[0xDEADBEEF]

Ya know what's wild? We have had zero issues running at PPIR which is a roval. While not a super fun track, holy crap that banking! There's really something to be said about hauling ass that close to a cement wall, you have to play chicken with it essentially. And the sound of the car when you get right next to it is so badass.

Banked turns? That would help a lot.

 

[Schurkey]

I have a switch on the dash to switch off the fuel pump when I'm running on LPG (propane). Cranking the engine for a bit before enabling the pump helps get the oil moving before the engine fires. Can't say it makes any difference or that I'm overly zealous with my cold start regime but I have the option to push some oil before the firing begins.

Wild Guess: That's worse than just starting the engine.

You're still spinning the crank and cam on whatever residual oil is on the journals; but with extra time spent wiping the cam lobes along the lifters, loading the lifters without oil pressure to "inflate" them, wiping the rocker arms on the fulcrums, etc. Residual oil is all you have for lube, and you're spending extra time stressing that film.

If the engine STARTS, the oil pump turns significantly faster, making it more effective in pushing oil through the oil galleries to the bearings, but also to the lifters, pushrods, valvetrain, etc.

Not to mention the reduced starter engagement time on the unlubed starter drive/flywheel teeth, and increased battery drain.