Here is an excellent video on Engine Masters about oil pumps comparison.....


https://www.motortrendondemand.com/detail/its-the-oil-pump-pump-off/3314259/12456


Just my $0.02...

'Skeptical' means I'm suspicious of its veracity. Not that I disagree. I can't accept it as true without evidence. Oil subjected to the G-forces of a drag race can pile up in the back of a pan, show low oil pressure, and have nothing to do with pumping the sump dry.

Looks like a new Melling, and that is what I did, I took out the pink spring and installed black one one from a older pump which seemed to increase the top end pressure a bit, and the speed of increase but idle pressure stayed about the same. I will try a straight 30w and see if it can give me above 20ps, I can live with that.

Not high volume but changing to a high pressure pump...would that bring up the idle pressure?

A high pressure pump is only one with a stiffer spring. Again, it will have no impact on your idle oil pressure. The spring simply sets the max pressure that is allowed and then all the pressure after than to sent back to the pan along with it's volume.

Ok thanks.I'm going to try the 30w and see if I can get a bump in pressure up to 20+.

Is this the same engine you had lifter problems with? If so what was the pressure before you went to the solid lifters?

Good question and yes it is the same pressure at idle, I didn't see any noticeable change and I'm using same oil Lucas Hot Rod 10W-40.

Lifters now sound a lot better as solid across the rpm range.

To increase hot pressure with increased oil viscosity, we would want the second number of a multigrade to go higher.

The second number of a multigrade indicates higher temp (212F) viscosity.
The first number relates to viscosity below freezing temperatures

Single Grade (SAE30, 40 and so on) also indicates viscosity at 212F, but cold viscosity falls wherever it may.

So....to experiment with a thicker viscosity when hot, if currently using 10w40, you would generally want to go to a __w50.

15w50 and 20w50 are pretty commonly available and that's what I'd recommend trying next if you wanted to do that experiment.

5w50s are available if you're concerned about cold weather performance. I've never seen 10w50 but am aware 10w60 is a common grade
in some warm weather locations outside the US.

Before I would waste a dime make sure that gauge is 100 percent correct. I would try another one just to be sure. Or you might be able to test it with air pressure along with a regulator and gauge. You would be pretty upset if you found it 5psi or more incorrect.

i wouldn't chase high pressure by itself. large rotor pump has more displacement which should get you to relief pressure sooner. do the 30wt and look for a filter that is 95% efficient rather than 99%, and don't get lost in the brand name; this is just an economical test. i like the black springs for higher pressure but don't think anybody makes them anymore.

Good suggestion trying a second gauge to insure accuracy, and I do have a second gauge and worth giving it a try. Its bran new in the box, just have to find it....

Main reason is I have seen many people here as well as other sites chase a problem only to find out it was a gauge accuracy issue. About the simplest and cheapest repair/test at this point. If the pressure is the same I would remove the pump and measure everything or just buy a new pump as they are cheap and easy to swap out. Heavier oil is just a band aid in my opinion.

My hemi has a melling HV pump on it and both it and a new 1 I have came with the plain color high pressure spring. With 10W-30 Mobile 1 it has 55psi hot at idle but the lowest I can idle with my solid roller is 1100 rpm. By 2,000 hot it's up to 75. It is 75 cold idle. Max pressure can get to 100. It was higher than I liked so I tried a standard melling with pink spring and it did lower idle but seemed to max out around 45 psi. Too low. So my only choices is to trim plan spring to lower max pressure or shim standard spring to increase pressure.

I wouldn't have any problem with your current pressures but if you want more at idle put a HV pump on it and use your pink spring since it gives you 60psi which is plenty.

I got a new gauge, its showing 30lbs at idle and its hitting almost 70lbs by 2000rpm.

Silly me, trusting an old test gauge, I won't make that mistake again.

Got a lot of good info from this thread, thank you all for the help!
Wolf

Wow that's good to hear. Almost unbelievable. To many times we are like horses with blinders on. Glad it worked out. I know I would be as happy as a Clam..

Glad it was something simple and easy

so which gauge do you believe? the one that reads high or the one that reads low? maybe try a third gauge to verify the other two? been here before and don't have a perfect answer.

i think i would try a third gauge if one were available.
now with that said, a hemi is an expensive piece of iron, so i would want to be absolutely, positively certain i could trust any information a specific gauge was telling me.
in a perfect world, an expensive gauge "would" be better than a cheapo version, but our world isn't exactly perfect by any stretch of the imagination.
figure this response another imperfect answer.

Pretty damn easy to test the gauges….fittings, an inflated tire, a few tire gauges…. You may even find a tire gauge you might own is way off.

L