Ford Racing 427W ate cam gear

[DAVID GAGNARD]

Originally Posted by Luce

David, that is not exactly apples to apples. A better example is your new, in spec engine has a total open clearance (not sure how you would measure such a thing) for discussions sake equivalent to a hole .2". If you push x gal/ hr through that hole, you will have y PSI of back pressure getting that much oil through that hole. Now open that hole to .3". If you increase the flow to some x', you can achieve the same pressure, but at a higher flow rate. The pressure is what assures that oil is getting everywhere. With some miniscule (maybe 2-5 PSI) you could maybe get some oil to the first main bearing, but not stand a chance of it getting up the pushrods to the rockers. A larger swept volume oil pump will hold the same pressure with a larger clearance and/or lower viscosity oil. A larger volume oil pump will also spend more time bypassing excess flow

No, not exactly apples to apples, but close...think about this: your oil pump pickup/tube is a specific diameter and can flow X gal/hr thru it,now the oil is sucked up thru the pickup in the bottom of your oil pan and into the pump, where it is pushed under pressure thru the oil filter and into a hole in the block feeding the engine oil....

Now, go look at the diameter of any stock or after market oil pickup and the look at the size of the hole in the block where the oil enters under pressure....I can assure the hole in the block is quite a bit smaller than the diameter of the pickup,it has to be,otherwise the pickup would not be able to flow enough oil to maintain the output of the pump.....
I'm not a fluid dynamics engineer,it is all regulated by the pump bypass setting...one could change that setting and achieve more pressure with a HV pump, but according to Melling, they are all sent out with the same setting....

David