I need some advice. My engine builder assembled my 499 stroker. The bearing clearances are on the loose side with the rods at .0026-.0027, and the mains are .0031-.0032 and number 3 bearing at .0034. I ran a standard psi/standard volume melling pump. Oil pressure at 6000 rpm on the dyno was at 53 psi, but the engine was only 160 f.

Before installing the engine I replaced the oil spring to a high pressure spring.

Now that I have the motor in the car and the ambient is 90f and running at 195f water, I can tell that the oil pressure is lower. At idle it is at 15 psi and 5000 rpm it is 53 psi. I haven't taken it to 6000 rpm yet but I can't see getting more oil pressure than that. When you increase the rpm the oil pressure does react quickly.

Is this okay to leave it like this or should I be looking at a high volume pump?

You could put the HV pump in there to see what it does. That is a fairly simple experiment to run. Sometimes the best solution is a HV pump with a standard spring, other times you need the black spring.

AndyF, I only have a 3/8 pickup. I am running a 7 quart pan with a good windage tray. Is the pick up okay?

I run a basic HV pump on my 493. I set my clearances a tad on the loose side as all the mains were about .003 and the rods in the .002 to .0025. I just looked close at my car friday as I took a 90 mile round trip and it runs about 30 psi when hot (195) at idle and about 70 PSI at 60 mph which is about 3200 rpm cruising down the road. I am using Valvoline 20W-50 VR1 racing oil though. Ron

Way better to have to much volume and pressure than needed I would install the high volume pump as is but inspect and clean it before use, and then see what pressures you end up with
I normally use that pump on all my Hi Po BB builds, I will trim some coils off the black spring if needed, IE a street and strip motor that will see 6500 RPM max I will shoot for 65 lbs at 6500 RPM with hot oil(160F+) on the dyno or in the car On your deal if you decide to reduce the pressure on the high volume pump do as AndyF suggested, remove the black spring and put in the other spring from the standard pump to see what that does for you I have added shims(thin flat washers that will fit in the bypass valve cup between the srping and cup) to a standard pump to icrease the bypass pressure.
Let us know what you decide and find out, it will help others on here

Gentlemen, thanks for all the feedback. I will try the high volume pump.

Can I run the standard MP oil pump distributor gear with the HV pump? Do I need to pull the distributor and oil pump gear to replace the pump. Or can I just pull the oil pump?

(1) I believe so but wait for the BB guys to chime in. (2) I would have the pump bolts barely snug then insert the intergear then final torque the pump bolts for dead on hex alignment. I want to ask what weight of oil are you running? I would want the lightest weight you can get by with & still have adequate psi

Hey RapidRobert, I am running 15w50

Alright & I ain't enough of an oil guy to know if that is thin or thick oil (or somewhere in between)

I agree the HV pump is a good solution. With the higher clearances you need more flow, especially hot idle. It has worked well for me on my 496 with 3/8" pickup. Usually the relief spring as supplied is about right though there can be variation.

The HV pump needs a strengthened drive gear for reliability. Key improvements are hardened hex, radiused transition from hex to shaft and pinned gear. Higher loads with the HV pump can fail the stock piece. Mancini and others have them.

Oil viscosity can be used to "tune" the pressure. Mine likes 15W40.

I run a stock drive on my HV pumps with no problems at all. And go ahead and try installing the new pump with the drive in place. Spin the pump back and forth as you slide it up into place so that the hex can align. If it fights you, you can always bump the engine over a bit to help align the hex.

Question; Does the HV pump have that much more resistance to turning than the std pump? It would seem that the pressure would impact the resistance more. At say 60# pressure, how much harder do you think it would be to spin an HV pump over a std pump?

the HV pump would probably help lower rpm volume but may not add a lot of volume in the upper rpm due to the 3/8" pick-up. anyhow, i use an HV pump with 1/2" pick-up and stock low pressure spring. hot idle in gear is 40lbs, running pressure 60lbs with 30wt oil. my bearing clearances are a little tighter.

me to for higher RPM/spirited driving I think adequate area on the suction side is important (1/2 pickup & a bit more mods upstream). I want adequate area (pressure side as well)/correct bearing clearances/correct (as light as possible) oil weight/bypasses as some journals can be starving tho the gauge at the beginning of the system (rear of the block) shows an adequate number) THEN see how much pump/spring I need to obtain enough psi

15w50 oil? That seems a bit overkill. I'd put some 10w30 in there and see where you're at. The thick oil is hard to pump so the engine doesn't get as much oil flow.

He'll have less pressure with 10w30. 10w30 and a HV pump might be the perfect combination though.

between loose bearing clearances and probably wide rod side clearance the bottom ends a "bleeder". this seems to be very similar to a build i had a couple of years ago. mine was 18psi hot idling in gear with a heavy base stock 30wt oil and half groove mains. i tightened the bearing clearances up (.0005"-.0007" tighter), got rid of half the rod side clearance (i will never believe side clearance doesn't effect pressure. it's a hole, it's a leak!) and more than doubled low rpm pressure (with added full groove mains) and the engine runs smoother

Same issue. Stock melling pump with the heavier spring. Running 15/40
Idles at 20pds hot and cruises around 6o-70 hot

You'll be fine with the 3/8 pick up.

If you insist on running the thicker oil then I would seriously consider upgrading to the HD oil pump drive ... i would do it no matter what oil ... it's cheaper than the cost of rebuilding the motor if the hex shears off.

John,if you knew what I have been running in my bird for 33 yrs you would be

Thanks everyone for all the great feedback. I will try the HV pump with 10w40. I ran 10w40 with the current pump and yes the oil psi was even lower.

Does anyone know if the Mopar Performance Distributor gear is a good match these HV pumps. The MP catalog does mention that it's hardened, or should I just order the Milodon distributor gear? Any other distributor gears that you guys recommend with HV pumps?