You seem to forget, you are running the pump on direct drive. Try the system when it is being run by the engine. It's run by the camshaft and is not direct drive and that is why it only runs at 3 to 6 lbs. Walt.

Frank here,
I didn't forget anything......Being gear driven from the camshaft [i][b]is [/b][/i]direct drive. There's no lost motion through the drive system in either scenario. The Duo-Flow is a gear driven, positive displacement, oscillating-piston pump. Nothing fuzzy there. Displacement X rpm yields output every time (with the minor exception of slight losses due to necessary internal clearances).
How long would you predict that a splasher would run with filters in place in each of the discharge circuits? Keeping in mind, of course, that they are full flow design, each capable of passing over 10 times the actual flow rate at 4000 rpm as a "worst-case" scenario.
I will agree that our engines will likely never see enough miles for filtration to be a significant factor in terms of life [i]time[/i], but I like to know that I'm minimizing avoidable wear as long as I'm in the driver's seat.
Frank

Being that the camshaft turns at half the speed of the crankshaft, what rpm is the pump turning at 2500 engine rpm?? Knowing that the oil pump gear is slightly smaller than the cam drive gear i am thinking that the oil pump rpm will be only slightly more than the camshaft rpm, correct?

The crank to cam ratio is, obviously, 2:1 and the cam to pump is 6:1 for a total reduction of 12:1. At 2500 crank rpm the pump will be turning at 208. These figures apply to the sixes and eights of the 30's and later, and presumably earlier engines, too, but I can't say for certain that the cam to pump ratio is the same on those. A little "research" would reveal the answer if anyone cared.
F

Frank is the man to listen to! It matters not what r.p.m. the pump shaft is turning, it is designed to deliver the exact quantity of oil the engine requires. The end of the pump shaft has an offset peg, which runs in a groove in the double-ended piston, which oscillates and and also partially rotates to uncover the intake and delivery ports. The oil is drawn by suction into the pump, and positively pumped into the engine. The main thing is to ensure that the intake pipe is absolutely air-tight. As to whether you actually need an oil filter on this type of system is a moot point. Hudson did offer such a filter as an accessory, but as far as I know never fitted them on cars out of the assembly line. It's like the old theory of throwing banana skins on the lawn to keep the tigers off - I don't get tigers on my lawn!
Geoff

I'll agree that filtration isn't an absolutely necessary feature in this "type of system" or any other lubrication system, but argue that it is a desirable one. Just my opinion, but it's one shared with a few others, current or past, who also don't view it as ""banana peels on the lawn", such as: Ford, GM, Toyota, Kia, Hyundai, Chrysler, Jaguar, Lamborghini, Lombardini, Caterpillar, Komatsu, Daihatsu, Deutz, Detroit Diesel, Honda, Mazda, Mitsubishi, Perkins, Peugeot, Volvo, Saab, Mercedes Benz, Bugatti, Navistar, Cummins, John Deere, Mack, Liebherr, AMC, Packard, Studebaker, Nissan, BMW, Fiat-Allis..............need I go on? Any one of them (and many more) would run just fine without that feature but there's apparently some advantage to engineering, developing and implementing it into virtually every engine design since the mid fifties......some prior.
I simply prefer to have my oil filtered [i][b]before[/b][/i] it reaches the moving parts of my engines, whether it's critically necessary or not. Others may do as they wish.
Just Frank's biased opinion.