80# Oil Pump Upgrade

37Flat

37Flat

Senior Member
I'm rebuilding a stock 221 for a daily driver (or at least once a week). I've installed a full flow oil system. Have read that an 80# oil pump is more efficient with the full flow. I have a 50#, but the price difference for the rebuild kit vs. new 80# is not so much if it's better insurance. Would appreciate any and all input.

Thanks

Chris
 
80 psi would be to much for engine bearings, but you have to consider the pressure drop of the filter. I wouldn't what to see more than 50 psi at the bearings. 30 psi drop through the filter seems like a lot, so I'm not sure but 80 psi seems a bit much. Keep in mind that it require energy to produce that 80 psi and that energy is taken away from the drivetrain. Be interesting to hear from posters with full-flow filter experience, but I just don't see the reasoning that supports these high oil pressure numbers, even 50 psi is high.
 
The relief valve in the oil gallery will set the pressure full flow or partial if left in there so using a 50 lbs spring and you have the original pressure.
 
flatheadmurre said:
The relief valve in the oil gallery will set the pressure full flow or partial if left in there so using a 50 lbs spring and you have the original pressure.
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Flatheadmurre:

Interesting post. I know Tardell and others recommend replacing the spring in the relief valve in the gallery with a heavier one. Do you do this as well?
 
flatheadmurre said:
The relief valve in the oil gallery will set the pressure full flow or partial if left in there so using a 50 lbs spring and you have the original pressure.
Click to expand...

That's true, but you are still requiring the oil pump to output 80 psi. I should have been more specific in my first post! I was meaning to say you are producing more pressure than can be used IMHO and as Ol Ron points out, you are just increasing oil temperature and requiring the oil pump to work harder than it needs to. You only need enough oil pressure to keep the proper spacing between metal and bearing surfaces, any pressure increase beyond than serves little purpose.
 
JSeery said:
That's true, but you are still requiring the oil pump to output 80 psi. I should have been more specific in my first post! I was meaning to say you are producing more pressure than can be used IMHO and as Ol Ron points out, you are just increasing oil temperature and requiring the oil pump to work harder than it needs to. You only need enough oil pressure to keep the proper spacing between metal and bearing surfaces, any pressure increase beyond than serves little purpose.
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The pump doesn´t produce more pressure then the lowest relief valve in the system let´s it.
What the shortbody pump produce more then the stock is flow.
 
flatheadmurre, we may be talking apple and oranges. The pressure will never be higher than the release valve value, but it still requires more energy and heat to get there.
 
Interesting information. So then heavier spring Mac's sells would allow the 80# pump to really over saturate the system? I'll stick with 50#.

Thank you all.

Chris
 
I think the important difference between the early and late pumps is that the late pumps have helical gears and are just better all-around units. The specification for the late pumps says that the relief spring should open at 57 lbs. Both of the flatheads I am currently running run at this pressure at speed. I think that referring to one as an "80#" pump and the other as a "50#" doesn't tell the entire story.
 
often wondered where the #80 lb pump got it's name as the relief valve is set for 55/60 lbs. I never rebuild these pumps because the rebuild kit comes from Mellings, which in my opinion make junk. However maybe they've changed. The stock pump regardless which one can be cleaned and inspected. If it has a problem find another. In my casr I have allot of them so that's nor a problem,. Most of these pumps just never ware out. Adding one of these pumps to an early engine adds another relief valve, I like to set the on in the pump higher than the one in the front of the oil galley , that way the front relief controls ALL the oil to the bearings and putting the relies in the pump was just a way to save money.
 
Can the experts explain why that front relief check valve has a flat spot located on the lower end of the ball? Looks like to me its always allowing oil to leak out in the area behind the cam gear.

Ronnieroadster
 
Ronnieroadster said:
Can the experts explain why that front relief check valve has a flat spot located on the lower end of the ball? Looks like to me its always allowing oil to leak out in the area behind the cam gear.

Ronnieroadster
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That's exactly what the flat spot is there for to keep oil to the timing gears. Wonder why they did away with it on the 49-53 8BA engines ?
 
I'm not a believer in a higher pressure pump. or helical gears for that matter. I think the stock 50# pump is just fine, and adjusted correctly will work great.
I use a stock, long style early pump with a slightly increased relief spring and make the
front relief (on an early style block) adjustable.

In doing so, I set the relief to 60# max. This gives me a startup pressure of about 50#, and hot running about 30-40# depending on RPM. Works for me
 
Ken/Alabama said:
That's exactly what the flat spot is there for to keep oil to the timing gears. Wonder why they did away with it on the 49-53 8BA engines ?
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Seems to me it was eliminated on the 49 to 53 engines because it was never needed. Theres plenty of oil windage taking place that allows oil to get onto the crank gear and cam gear.
On all the early engines I build I always eliminate the front relief valve this improves the oil flow to the front of the engine and we have never seen any ill effects from the lack of the oil bypassing to the cam gear area. Relying on the relief valve in the oil pump has always worked perfectly for the way I do it.
 
Ken/Alabama said:
That's exactly what the flat spot is there for to keep oil to the timing gears. Wonder why they did away with it on the 49-53 8BA engines ?
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I believe it is also there to get oil to the bushings on the water pumps. I can't see (in my mind's eye) where the oil comes into those little oil passages on the front of the block . . . but I seem to remember it was related to the oil coming from the pressure valve and the 'flat' on it.

In 49-53 they pumped oil through the camshaft front bearing journal to lubricate the thrust surface and gear on the cam snout - which also probably lubricated the timing gears. Also, I believe that the later water pumps no longer used bushings and the two 'oil holes' are no longer in the blocks - this is probably also related to why they got rid of the front-mount pressure valve and 'bleeding' flat.
 
The timing gear throws out the oil into 2 small catchpockets from where the oil feeds the pumps through the holes in the front of the block.
 
flatheadmurre said:
The timing gear throws out the oil into 2 small catchpockets from where the oil feeds the pumps through the holes in the front of the block.
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Yep - now you refreshed my mind! I knew that the bushing oil feed was not under pressure . . . just couldn't remember where the oil was 'slung' too up in the timing gear area.

Thanks!
 
Someone stated that if you do not block the little holes you will have an oil leak in the front of your engine. I asked Speedway tech about blocking the hole & he said it wasn't necessary with their bearing pumps.
This if you have the water pumps with bearings instead of bushings.
 
I have looked all over for the recommended relief spring "blow-off" pressure for an 8BA. I finally found it in an old "Motor" manual from 1960 that still has a section on flatheads. That manual says the relief should open at 57 psi. I could not find this information on any of the Ford sources I have perused. Does anyone have any better information (say, an official Ford source)?

Also, since I am asking obtuse questions, is that figure available for the earlier engines? Perhaps full-floating bearings require less pressure? What about poured Babbitt vs. insert bearings? If there is a difference, it might reflect upon the wisdom of installing a later pump in an earlier engine.
 
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