Question on my oil pressure readings-happy father's day

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It's in the port by the distributor but I tightened it slightly while it was running yeaterday just to see and it stopped, not sure if it needs to be tightened more and it's a stainless steel -4 an line. Saw maybe a 2psi pressure difference but maybe needs to be tightened more. I'll be able to do more work on Wednesday

you also said you have 6K on this present oil change, or did I read that wrong?
 
you also said you have 6K on this present oil change, or did I read that wrong?
No no I would never I always change my oils at 2800 or so. If I wrote it wrong my apologies. I've very on point with my car and engine maintenance, I write everything down. The engine has had 4 oil changes since break in but only has about 6000 on the motor in general in just cause I wanted it to clear out anything in begining after break in
 
No no I would never I always change my oils at 2800 or so. If I wrote it wrong my apologies. I've very on point with my car and engine maintenance, I write everything down. The engine has had 4 oil changes since break in but only has about 6000 on the motor in general in just cause I wanted it to clear out anything in begining after break in

What filter is on it?
 
Has the oil pressure been the same since the rebuild.
The pressure the engine is producing is more in line with what a standard pump puts out.
 
Has the oil pressure been the same since the rebuild.
The pressure the engine is producing is more in line with what a standard pump puts out.

That's a very good point. Mark, how SURE are you that it is a HV pump?
 
I use a standard pump with high pressure spring on my big block street car.
45 psi at 950 rpm idle and 70 psi at 2000. rods and mains on the loose side.
 
It is a hv melling pump,I remember having to clearance the body for the stud and it was a *****, my dad said I should drop the pan and check it out first. It might of came loose he is thinking, like he pointed out I should have higher oil pressure. Maybe they accidently sent me a standard in a hv box? I have pictures in going to look now and see if they're is anything that doesn't look right
 
Cold start pressure is 60-65

I've seen HV pumps peg 100 on cold start. I'm beginning to think you may have an issue after all. AS LONG AS you do end having an HV pump. You seem pretty confident that's what it is.
 
I've seen HV pumps peg 100 on cold start. I'm beginning to think you may have an issue after all. AS LONG AS you do end having an HV pump. You seem pretty confident that's what it is.
That's where I'm leaning.
Just about all the engines I've been involved with using the HV pump had 90-100 at cold start.
 
I didn't put loctite on pump stud nuts and I did have clearance issues when I put it on I'll grab the picture so I'm thinking maybe it came loose or something going on down there. My dad pointed out my pressure should be better even with clearance I have
 
This was the issue I ran into and I grinded away some of the body so maybe I didn't grind enough or it came loose, I think it'll be good for my to drop the pan regardless just a pain to do so but gotta be done that way I can see what's going on

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That oil pressure is fine. Zero need to use another oil looking for more pressure. That's absolute nonsense. What's the pressure at say 2000 RPM? That's where most factory service manuals give the spec.
The factory service manual is only good for a stock build with stock hydraulic and adjustable rockers. Rollers rockers bleed off a lot of pressure at idle. The stock engines never demanded the oil flow and pressure a performance let alone what a race build needs. I would never use a stock pump if I’m using roller rockers. Take into account that the cam bearings are almost never put in correctly, meaning lined up perfectly. Kim
 
This was the issue I ran into and I grinded away some of the body so maybe I didn't grind enough or it came loose, I think it'll be good for my to drop the pan regardless just a pain to do so but gotta be done that way I can see what's going on

View attachment 1715754519

I'm endorsing that move.
 
Did you use a gasket between the pump and cap? I do, but I’ve seen them fail because the cap or the pump (or both) weren’t flat.

BTW, if you aren’t using a gasket between the pump and the cap you SHOULD be. Some Melling engineer gave a webinar and I asked that specific question and the answer was absolutely yes.

EDIT: I forgot to mention the correct fix (IMHO) is to machine the main cap down ad use a shorter bolt or stud for that position. Any dullard with a mill can take .125 or so off and then it’s fixed forever.
 
Let’s not forget that the heavier the oil the bigger the molecules are so the better the cushioning is for the larger clearances. Hope I said that right. Kim
 
Hey guys I know I have went over this in the past but I wanted to touch base and get some opinions. So if u don't already know I have a brand new built 340 to 373 stroker. Bearings across the board were .0025. I currently run 10w40 lucat hot rod oil. Engine now has hit the 6000 mile mark. When hot idling at a light 850rpm I'm seeing 20-22 psi. Is this normal and also if not should I go to a 20w50? I live in CA so we have warmer weather as well. Car temp usually sits at 185-190 fully warmed up. I'm just concerned on the oil pressure. Please let me know what u guys think? Also happy father's day
in my opinion its too low before u put in a heavery oil put in a high pressure / high volume pump there is a old wise tail that holds true 10# of oil pressure for every 1000 rpms . now there r thr guys that will say if u have 95# of oil pressure (in a bb ) is too much oil pressure it slows the motir down so they restrick the oil & blow the motor up. i ran a 400 b motor for 13 yrs on & off the track i had 95# of oil pressure just about all the time & I NEVER SPUN A BEARING (IT RAN 115 IN THE 1/4

charles (2).jpg


Charles last race.jpg
 
My old duster ran 11.001 for 20 years. The gauge pegged past 100 lbs cold. Warn idle was 65 lbs. going down the track it was pegged again. Never had a problem. 440 with 6 pac rank, rods and pistons. 915 heads adjustable rockers. Super stock cheater cam DC oil pump with the spacer kit. Kim
 
My old duster ran 11.001 for 20 years. The gauge pegged past 100 lbs cold. Warn idle was 65 lbs. going down the track it was pegged again. Never had a problem. 440 with 6 pac rank, rods and pistons. 915 heads adjustable rockers. Super stock cheater cam DC oil pump with the spacer kit. Kim

Oh it just couldn't have made all that power with those heavy *** rods. <rolls eyes> lol
 
Okay but is 20psi at hot idle 850rpm necessarily bad?
Not at idle when the pressure comes right off idle.
The older Detroit Diesel engines would idle at 5PSI. These were prior to common turbocharging and had about 20:1 CR. They would run for years like that. As soon as you reved them a bit the pressure would climb up to about 40PSI.
 
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