Originally Posted By: BuickGN
You guys going back and forth has taught me a lot. I've always run a high volume pump even though the fast guys told me not to. This was in an attempt to raise my idle pressure which it didn't help much, it just put me on the pump bypass at 3,000rpm instead of 4,500rpm. Now it makes more sense to run my stock pump and save the front cam bearing.
What I've concluded about HV oil pumps is that they are only good IF your engine is modified to flow more oil.
Fact is, if you put a HV pump on a bone stock engine (stock flow resistance), and that HV has a relief pressure the same as the OEM pump (say 80 psi), then you are gaining nothing at all. The stock engine setup will flow the exact same oil volume (at some viscosity at X temp) at 80 psi REGARDLESS if the pump is HV or OEM, as long as the pump can supply adequate volume. With the HV, it just means MORE excess volume is shunted to the sump via the relief valve. The only time a HV pump will flow more on a stock engine is if the relief pressure is higher than the stock pump was.
The other alternative is to change the relief setting on the OEM pump. When doing that mod, this causes MORE flow volume at higher RPM because you are putting more pressure on the system, which makes more volume flow through the filter/engine. Of course, it you run the pressure too high, then you have other issues to address ... like filter strength, seal leakage, etc. The same would have to be considered if running a HV pump with a much higer pressure relief setting.
You guys going back and forth has taught me a lot. I've always run a high volume pump even though the fast guys told me not to. This was in an attempt to raise my idle pressure which it didn't help much, it just put me on the pump bypass at 3,000rpm instead of 4,500rpm. Now it makes more sense to run my stock pump and save the front cam bearing.
What I've concluded about HV oil pumps is that they are only good IF your engine is modified to flow more oil.
Fact is, if you put a HV pump on a bone stock engine (stock flow resistance), and that HV has a relief pressure the same as the OEM pump (say 80 psi), then you are gaining nothing at all. The stock engine setup will flow the exact same oil volume (at some viscosity at X temp) at 80 psi REGARDLESS if the pump is HV or OEM, as long as the pump can supply adequate volume. With the HV, it just means MORE excess volume is shunted to the sump via the relief valve. The only time a HV pump will flow more on a stock engine is if the relief pressure is higher than the stock pump was.
The other alternative is to change the relief setting on the OEM pump. When doing that mod, this causes MORE flow volume at higher RPM because you are putting more pressure on the system, which makes more volume flow through the filter/engine. Of course, it you run the pressure too high, then you have other issues to address ... like filter strength, seal leakage, etc. The same would have to be considered if running a HV pump with a much higer pressure relief setting.