Ford Racing 427W ate cam gear

[zrayr]

Originally Posted by DAVID GAGNARD

This statement is a misnomer and false and something people should understand and get correct.......

All a high volume oil pump does is pump 30% (depends on the pump,some put out 25% more) more oil than a "standard volume" oil pump.....The oil pressure remains the same with either a high volume or standard volume pump, the only thing that changes is the volume of oil pumped!!!!!!!...."

David

Sorry, but you are 100% wrong. If engine clearances stay the same, and they do, they the oil pressure goes up with the HV pumps. I've taken out numerous std. pumps from all types of Ford engines, and installed Melling HV pumps in their place. You can expect a 15 to 25 psi increase in hot oil pressure after the swap.

Z.

[DAVID GAGNARD]

Originally Posted by zrayr

Sorry, but you are 100% wrong. If engine clearances stay the same, and they do, they the oil pressure goes up with the HV pumps. I've taken out numerous std. pumps from all types of Ford engines, and installed Melling HV pumps in their place. You can expect a 15 to 25 psi increase in hot oil pressure after the swap.

Z.

I do understand what you are saying and it does make sense. I've had this very same discussion with the people at Melling that build the pumps,so there are 100% wrong also....... according to the people at Melling, their standard volume and their high volume oil pumps are set at the same psi and rated for the same psi, only difference is volume of oil being pumped by the pump... I asked the same question you have answered in the above post, their answer was the pump itself will only pump X amount of pressure,once that is exceeded the bypass kicks in....
I don't doubt you did get more oil pressure with a HV pump, some of that could be attributed to changing pumps in a used engine with Y amount of wear in the bearings,in that case you would get more pressure because of the increased flow of oil....the only real way to find out would be to run a new engine with each pump as see what the oil pressure would be with each pump......
Also, the Melling pumps I use have are adjustable and one can turn up or down the adjustment to set at what pressure the bypass "kicks in".

David