KV100 is irrelevant to the oil pressure. The oil pressure is determined by HTHS, and the flat-tappet wear protection is determined by the base-oil viscosity HTFS and AW/EP/FM additives. See my table linked above.
Oil for boosting oil pressure in 1950s V8
- Thread starter Fabulous50s
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High on Amsoil and I understand... but you don't need it.
I would test the Mobil1 4t 10w40 motorcycle oil. If you're happy with the PSI with it, then no need for a 20w50. If not PSI happy, the next step up would be Mobil1 15w50. Since these are easy enough to locate locally, once you find the happy grade, get the same grade in Amsoil or whatever brand.
https://www.mobil.com/lubricants/-/...engine-oils-product-guide-sheet--may-2022.pdf
I would test the Mobil1 4t 10w40 motorcycle oil. If you're happy with the PSI with it, then no need for a 20w50. If not PSI happy, the next step up would be Mobil1 15w50. Since these are easy enough to locate locally, once you find the happy grade, get the same grade in Amsoil or whatever brand.
https://www.mobil.com/lubricants/-/...engine-oils-product-guide-sheet--may-2022.pdf
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Just checking my records of what i measured on assembly for bearing clearances. Mains were 0.0018"- 0.0023"
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Yes, crank was a reman 0.010 under factory crank. Oil pump shaft broke and spun #1 and #5 rod bearings. I replaced 3 rods with NOS I bought on fleabay.
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Yes, I printed the chart off actually. I just don't know what I'm looking at very well. The more I read (especially on here) the less I know! I'm doing my best to understand what the numbers all mean.
The pds shows 14.9.
OVERKILL
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Most of my experience is with Windsors, and that would be very low for a Windsor. All my 302's have been in the 30's hot at idle and our 351W in our boat is there too. But heck, even our old 312 Y-Block was 20-something at idle with M1 5W-30 in it.
Last time I saw 10psi at idle on a Windsor, all the rod bearings were down to the copper, hahahah.
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Don't worry about the Gokhan university. That info isn't needed.
Just move up the SAE grade and pick an oil with an appropriate z/p for your 'peace of mind', and why I listed the M1 datasheet link.
Neither will break the bank for testing purposes. What filter and partnumber are you using?
https://www.walmart.com/ip/Mobil-1-Racing-4T-Full-Synthetic-Motorcycle-Oil-10W-40-1-qt/16767829
https://www.walmart.com/ip/Mobil-1-Advanced-Full-Synthetic-Motor-Oil-15W-50-5-qt/20713647
https://www.walmart.com/ip/Mobil-1-V-Twin-Full-Synthetic-Motorcycle-Oil-20W-50-1-qt/16767830
OVERKILL
$100 Site Donor 2021
That video is exactly what I was thinking, that maybe there was a good sized internal leak somewhere.
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If it was my car, I'd probably pull the engine and put a high volume pump in it just because I know it would bug me a lot in a fresh engine. That said, I had a 65 F-250 with a 352 FE that I ran for years that had low enough oil pressure that the oil light would flicker at idle. I ran 20w50 in it, BTW.
Is it this pump? Are the instructions applicable?
That's oversimplification and refusing to learn things. The same SAE grade is allowed to have different HTHS, base-oil viscosity, and VII content. You can have a Euro 5W-30 as thick as a SAE 40 or a SAE 20W-50 thinner than a SAE 40.
HTHS is what matters for the oil pressure, and the base-oil viscosity, which is what I call HTFS in my table, is what matters for flat-tappet wear or valvetrain wear in general.
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Are you still running the factory rockers & shaft setup? If so, that is likely where your oil is going. These engines have a tendency to over-oil the valve train, especially if the rest of the engine is at-spec. and there is some extra clearance in the rockers.
"Move up a grade" is not the answer here. With those clearances, it could run on 5W-20. The issue isn't viscosity. I retract my last statement where I said I don't see an issue. If the OP had 10 psi hot idle with a 5W-20 matching that clearance, I wouldn't see an issue. If the clearance was .0030-.0034" with the 10W-40, I wouldn't see an issue. The fact that it's 10 psi hot idle with .0020" clearance and a 10W-40 is worrisome.
This is pointing to a fault in the oiling system, something like the pump bypass is stuck open or there's a missing oil galley plug. Either case means reduced oil flow to the bearings and top end of the valvetrain. If you go dumping a more viscous oil in there, with an issue like a missing galley plug, you'd be reducing that flow even more.
With the engine idling, check to see if there's excessive oil accumulation in the heads / under valve covers. If not, you'll need to dig deeper.
If I had it, I would pull the pan and check the main and rod bearings, verify clearance, test the pump and bypass, and then pull the timing cover to check the oil plugs.
Again, higher viscosity oil is NOT the answer here. There's an internal fault that needs to be found. I'm iffy to say the oil restrictors are the cause as I've left them out and had sufficient pressure still (with the appropriate viscosity) though it's still a possibility.
This is pointing to a fault in the oiling system, something like the pump bypass is stuck open or there's a missing oil galley plug. Either case means reduced oil flow to the bearings and top end of the valvetrain. If you go dumping a more viscous oil in there, with an issue like a missing galley plug, you'd be reducing that flow even more.
With the engine idling, check to see if there's excessive oil accumulation in the heads / under valve covers. If not, you'll need to dig deeper.
If I had it, I would pull the pan and check the main and rod bearings, verify clearance, test the pump and bypass, and then pull the timing cover to check the oil plugs.
Again, higher viscosity oil is NOT the answer here. There's an internal fault that needs to be found. I'm iffy to say the oil restrictors are the cause as I've left them out and had sufficient pressure still (with the appropriate viscosity) though it's still a possibility.
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I'd run Mobil 1 15W-50 and forget about it.
These old pushrod engines don't need a ton of oil pressure, flow however matters.
These old pushrod engines don't need a ton of oil pressure, flow however matters.
I would put a set of 90 Holley jets in the rocker feed holes though 10 isn't horrible the low oil pressure light comes on about 7psi.
If you change the pump get one from Doug (AKA PumpBuilder)
Have you posted on FE power?
If you change the pump get one from Doug (AKA PumpBuilder)
Have you posted on FE power?