98 oil pump for 95 6.5 (929) block?

[jerry598]

Read in somebody's post (can't find it now) suggesting the 95 oil pump could be replaced with a 98 pump during a rebuild to increase running oil pressure. So.... I ordered one.

Now I'm wondering if that was so smart.

Will the oil cooler bypass and oil filter bypass valves in the 95 block function properly with a higher pressure pump? And, would the 95 oil cooler and cooler lines handle it OK? The oil pan in the 95 and the 98 are the same, according to the parts catalog.

Would there be any other weak spots in the 95 (929) oil gallery that might be affected by the higher oil pressure from a 1998 oil pump?

[JohnC]

The 98 pump is a higher volume pump, not a higher pressure pump. the higher volume was intended to compensate for the piston oil spray nozzles.

Pressure in the system is set by the oil pressure relief valve. If you force more volume through the system, it may overwhelm the relief valve resulting in higher oil pressure, but it wouldn't be well controlled.

The bigger oil cooler lines are there to prevent a pressure drop due to the greater volume being forced through the smaller lines.

Bottom line? It probably won't make much difference one way or the other. The engine won't appreciably benefit from higher oil pressure, so I wouldn't bother.

[john8662]

Won't hurt, I've done the exact thing, in a 929 block as well. The only offset is that the HO pump cost double what the standard one and new screen do.

J

[jerry598]

Thanks for the clarification. You're right about the cost of the pump. Guess that should be my first consideration.

[Robyn]

I have the HO pump on my DaHooooley build (929) but I used the pump off the 506 squirt block as it was in fine shape.

I took the pump all apart, cleaned it well and reassembled it.

Had I been buying a fresh pump I would have bought the Std pump for the 95 engine as was mentioned,the engine wont get any real benefit from the HO pump.

You will see running pressure at about 60 PSI instead of the normal 40 and it will Idle a tad higher too.

A buddy of mine did his 6 and a half with the HO pump and its fine with it.

The DaHooooley had the standard oil lines that it came with and a 97 crate engine (506 squirter that puked) and it was sweet.

Robyn