Best oil pump and pump drive shaft.

dcurtis

10 Year Member
Jan 19, 2006
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Well I finally decided to pull my engine due to no oil pressure for the second time, first was due to a popped oil galley plug, this time the oil pump locked up and twisted my arp shaft off, first drive since i replaced the galley plug, so I was just wondering what is the best pump and shaft to buy this time, should I go high volume with a bigger pan or will standard pump and stock pan be fine, its a 347, rpm2 intake, 190lphr fuel pump, 30lb injector, 70mm tb, 75mm mas, afm n51hr, scorpion rollers, tfs 170's, shorty headers, 3,000 to 3,500 stall aod with 373's. Already pulled the front 3 galley plugs and threaded them to keep them from popping again.
 
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I don't know if it gets any better than the ARP shaft. Was there something lodged in the oil pump that caused it to seize? Possibly a missing oil galley plug from the last go around?

Joe
 
ARP shaft with a standard volume pump. Just don't screw it up this time. ;) Make sure everything is 100% clean and at minimum run oil through the pump before you install it.

High volume pumps don't really offer any benefit, especially in a mild setup like that. All they do is put more wear on your distributor/cam gear.
 
Don't let anyone try to fool you by telling you that a high volume oil pump will pump the pan dry or wear out the distributor gears. Read and learn from the people that make the best oil pumps...



Thanks to Stangnet member bubba-dough for helping to educate all of us by finding this article... :nice:

http://www.mellingengine.com/Portals/5/pdf/pdf_catalog/high-volume-pumps.pdf You will need the Adobe Acrobat viewer which is also a free download – http://www.adobe.com/products/acrobat/readstep2.html

From the Melling site, for those who didn't follow the link & read the tech note...

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High Volume Pumps: Advantages, Myths & Fables

Most of the stock automobile engines are designed to operate from idle to 4500 RPM. The original volume and pressure oil pump will work fine in this type of application. As the demands on the engine increase so does the demands on the oiling system and pump.

The oil pump's most difficult task is to supply oil to the connecting rod bearing that is the farthest from the pump. To reach this bearing, the oil travels from three to four feet, turns numerous square corners thru small holes in the crankshaft to the rod bearing. The rod bearing doesn't help matters. It is traveling in a circle which means centrifugal force is pulling the oil out of the bearing.

A 350 Chevy has a 3.4811 stroke and a 2.111 rod journal. The outer edge of the journal travels 17.5311 every revolution. At 1000 RPM, the outer edge is traveling at 16.6 MPH and 74.7 MPH at 4500 RPM. If we take this engine to 6500 the outer edge is up to 107.9 and at 8500 it is 141.1 MPH. Now imagine driving a car around a curve at those speeds and you can feel the centrifugal force. Now imagine doing it around a circle with a 5.581, diameter.

The size of the gears or rotors determines the amount of oil a pump can move at any given RPM. Resistance to this movement creates the pressure. If a pump is not large enough to meet the demands of the engine, there will not be any pressure. Or if the demands of the engine are increased beyond the pumps capabilities there will be a loss of oil pressure. This is where high volume pumps come in; they take care of any increased demands of the engine.

Increases in the engine's oil requirements come from higher RPM, being able to rev faster, increased bearing clearances, remote oil cooler and/or filter and any combination of these. Most high volume pumps also have a increase in pressure to help get the oil out to the bearings faster.

That is what a high volume pump will do. Now let Is consider what it will not do.


It will not replace a rebuild in a worn-out engine. It may increase pressure but the engine is still worn-out.

It will not pump the oil pan dry. Both solid and hydraulic lifters have metering valves to limit flow of the oil to the top of the engine. If a pan is pumped dry, it is because the holes that drain oil back to the pan are plugged. If the high volume pump is also higher pressure, there will be a slight increase in flow to the top.

It will not wear out distributor gears. The load on the gear is directly related to the resistance to flow. Oil pressure is the measure of resistance to flow. The Ford 427 FE "side oiler" used a pump with relief valve set at 125 psi and it used a standard distributor gear. Distributor gear failures are usually caused by a worn gear on a new cam gear and/or worn bearings allowing misalignment.

It will not cause foaming of the oil. With any oil pump, the excess oil not needed by the engine is recirculated within the pump. Any additional foaming is usually created by revving the engine higher. The oil thrown from the rod bearings is going faster and causes the foaming. This is why high performance engines use a windage tray.

It will not cause spark scatter. Because of the pump pressure there is a load on the distributor gear. The number of teeth on the oil pump gears determine the number of impulses per revolution of the pump. In a SB Chevy there are seven teeth on each gear giving 14 impulses per revolution. At 6000 RPM the oil pump is turning 3000 RPM or 50 revolutions per second. To have an effect on the distributor, these impulses would have to vibrate the distributor gear through an intermediate shaft that has loose connections at both ends. Spark scatter is usually caused by weak springs in the points or dust inside the distributor cap.

High volume pumps can be a big advantage if used where needed. If installed in an engine that does not need the additional volume, they will not create a problem. The additional flow will be recirculated within the pump.
 
What are your bearing clearances? Main, rod, rod side clearance? What brand oil pan and what size pickup? What is your valve spring pressure? How many rpm are you turning?
 
I just ordered another arp shaft and a melling m10687, i think that was the part number, i also have another m68, which pump would be better, not sure on the clearances, a well known shop about 40 miles from me done the bottom end, they run a 800 horse 67 mustang so they know fords, stock pan, stock pickup, and the trickflow heads have the original springs on them, not sure on the pressure of them, rpms wise it has the factory limiter so 6250, but i re-installed the galley plug, fired it up, let it warm up, left my drive way about 30 feet out of my driveway i hit the throttle, it hit about 4,000 pretty fast and i let out and instantly lost pressure. gonna pull the pump apart and look for something wrong with it, it almost looks like where the shaft goes into the pump is locked to the casing of the pump, like it swelled, is that possible. It isnt the plug that popped out causing it, when i replaced it i got a magnet and pulled it from the pan, it was right beside the pump.
 
Id use a 10687 or 10688 (which is a high volume, 25% more)...the supplied shaft is hardened or a Ford Racing or ARP shaft. You may need to smack the pan a little to gain clearance.

If the pump locked up something is stuck inside...
 
Well I pulled the pump apart and after prying the 4 pointed gear away from the 5 point gear there was what looked like gasket material wedged in there causing the lockup, just waiting.on the new one, hopefully she will be running this weekend. Also got a new pickup for it, and gonna
clean the hell out of it, I've now learned that something very small can cause me to spend 300 bucks so it will be clean enough to eat off when I reassemble it.