Oil Pressure at idle

[karolko]

I know this is a fairly general question, but I was wondering what oil pressure you Stage guys are running with your setups at idle and at operating temps ( 130-150 degree oil temps)

I have a Peterson R4 external pump and I need to adjust the pressure since it's idling at roughly 45psi.

I am running 10W30 VR1 oil with some Lucas Stabilizer in there.

Any help or guidance would be great. I don't know what a safe value would be at idle, but I do think that 45 psi is too high.

Adrian

 

[Mike E]

I'm running the same pump and making ~30 psi at idle warm with Brad Penn 20/50. Cold it might be 80-90. The pressure screw should only affect max pressure. How fast are you driving the pump? I'm driving mine at 1/2 engine speed. If I remember right, I have a 16 tooth crank, 32 tooth pump pulley. Mine idles at 1000rpm due to the lifters I have.

I wouldn't be concerned at all with 45 at idle. With a belt driven pump, the only downside to too much pressure is to much oil up top at high rpm. With a distributor, wear on the distributor gear or cam thrust is a concern, but that's not a problem with the belt drive pump.

 

[karolko]

Hey Mike,

When I ordered my pulleys from Jones he set me up with a 24 and 35 tooth, which works out to 68%.

I wonder if I am spinning it too fast. If I remember correctly, I read somewhere that it is best to run these things at 53-56%.
I never knew that the adjuster screw only adjusted max pressure.

 

[Mike E]

I bought my pulleys from Peterson and that is how fast they told me to spin the pump. As far as I know the pressure relief is only max pressure, but I could be wrong. Call and talk to Pat at peterson and he can tell you for sure.

 

[karolko]

Okay little follow-up question:

Does anyone know how you know what our engine requirements are, in GPM of oil, for our Stage motors?

 

[karolko]

I pulled this off Facebook written by Peterson Fluid Systems:

Tech Tip:
Pump pulley speeds:
In most drag racing applications your want to spin the pump as quickly as possible without exceeding the pumps internal limitations. Spinning the pump too fast can cause cavitation. There's a pump speed window that we set oil pumps to run within, this window varies by each engines individual max rpm range
.
An engine that spins 10k will only need a ratio of roughly 50-53 percent of engine speed. Where as an engine that only spins 6500 will need a ratio in the upper 60 percentile or lower 70's. In some diesel pull truck applications we can get as high as 80 percent pump ratios just because the motors don't turn high rpms at all. The maximum pump speed we like to see with our R4 pumps is around 5500 rpm. With our R4 it's not the rotors that cavitate, they're very efficient in their design. Above 5500 rpm the bearing longevity is what becomes a concern. Bearings support the oil pump shafts in each body, if they go out or tie up the pump shaft will scar and could possibly cause the shaft to snap completely. Just to be safe we commonly set them up around 5200 RPM pump speed just to err on the side of safety with your engines lively hood in our hands.
The other thing you MUST take into consideration is making sure we can get a belt on the set up. We can manipulate pulley sizes while still keeping the same ratio between the two just to get a belt to fit nicely in the pump adjustment range.
In dirt circle track bell-housing mount applications the crank gear is nearly always a 22 tooth HTD. We run anywhere from 38 - 44 tooth set ups depending on what the engine is telling us through out the race. The common belt sizes with this are either a 640mm HTD or a 632mm HTD belt for a Bert/Brinn setup.

 

[SNKSKNR]

Hey Mike,

When I ordered my pulleys from Jones he set me up with a 24 and 35 tooth, which works out to 68%.

I wonder if I am spinning it too fast. If I remember correctly, I read somewhere that it is best to run these things at 53-56%.
I never knew that the adjuster screw only adjusted max pressure.

LD

 

[SNKSKNR]

LD

Could you post a picture of the oil pump set up? I just got a box of parts and no idea on how it mounts up. Thanks

 

[NY Twin Turbo]

I have the Duttwieler set-up. Hot idle is at 35-37 lbs.