High volume oil pump.

I ordered one of those a while ago and had to wait. They had none in stock at the time I ordered so I had to wait till they did another run of them. It's in the luck of your timing but as far as I'm concerned, well worth it. Hope you get lucky!
 
What does a high volume oil pump accomplish other than putting more oil in the valve chamber, which immediately spills over onto the timing gears and falls back into the pan, is pumped back up into the valve chamber, where the excess volume flows over the timing gears and back into the pan and................?
 
High Volume Oil Pumps are normally used on a high RPM Racing Engine that is set up with more Oil Clearance to flow more oil to cool the bearings.
It also robs the engine of power as it takes more power to pump more oil.
I feel that a Normal Model A engine used at its intended RPM speeds is completely fine with its Original Oil Pump Capacity.
Just my 2 Cents.
 
Using a clear plastic lifter cover drain back tube on a fresh rebuilt engine with fresh stock pump I have discoverd that at higher rpm the pump will drain the pan faster then the oil can return. At low rpm the tube shows nice flow about 1\3 its volume. At higher rpm this flow will start to " pulse" telling me the pump is draining the sump at times and all the oil is circulating. I think a good stock pump is more then enough unless you are pressurizing the mains or have made other modifications.
 
A Model A oil pump is just a 'lift pump'. All it does is pump oil up to the valve chamber and gravity does the rest.
 
An engine with a drilled crankshaft that is set up for full pressure to the rod bearings and possibly other oiling mods would benefit from such a pump. If the high volumn pump is used on a stock model A engine it would cause worse oil leaks .
 
George D said:
Using a clear plastic lifter cover drain back tube on a fresh rebuilt engine with fresh stock pump I have discoverd that at higher rpm the pump will drain the pan faster then the oil can return. At low rpm the tube shows nice flow about 1\3 its volume. At higher rpm this flow will start to " pulse" telling me the pump is draining the sump at times and all the oil is circulating. I think a good stock pump is more then enough unless you are pressurizing the mains or have made other modifications.
Click to expand...

Clever idea! ...and good info too. Thanks!
 
OK, I said I ordered one. In fact, I already had one fitted in the motor in my Phaeton, the car we use for towing a camper around. That motor has inserted bearings, 5.5:1 head, downdraught carby, counter weighted crank and slightly modified cam. The high volume pump was not installed for the extra volume but so I could pressure feed the middle main bearing. that is the only bearing I force feed. I made a pressure relief valve set at 25 psi (the pump has one built in set at 50psi). With new oil, it maintains 26 psi all day long according tot he gauge. High volume is not the only use for these pumps. I regard them as a must for pressure feeding the bearings.
BTW, I have been told by some who should know that drilling a Model A crank for pressurising the mains will result in a broken crank shaft. Others say It depends on how it is done. A little hijack here - what is the experience out there? I know the original Model A cranks can break - I caught one just in the nick of time a few years ago. I replaced it with a Burlington counter weighted one and made the mods listed above.
 
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