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440 oil pressure too high ?

Hubbarocks

Hubbarocks

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hi guys, i know it was recently discussed on someone else's thread this year but didn't want to hi-jack his thread, so i started my own. i rebuilt 3 years ago , i don't recall the bearing clearances but were in specs of the plastic gage i used vs manual, i know that doesn't help. in hindsight i should have written down the results. The engine been around these numbers since i dropped in the motor 2 seasons ago. I'm not sure if I'm just staring at my oil pressure gauge too much instead of the speedo .. i may be fine but wanted to check with the group :) any reason to be concerned with these numbers? i suppose i could swap with a stock meling ...

autometer , electric gauge
440 / 727
meling high volume pump & 7 qt pan.
brad penn 10w40

start up / cold idle in park 80 psi

hot numbers
idle in park 45~50
idle in drive 35~40
cruise @ 60 mph (2800 rpm) 80-85 psi
cruise @ 40 mph 70-75 psi
@ WOT i can see it hit 90

thoughts appreciated.
- hubba
 
looks normal to me . mine is almost the same . and happy for it .
 
You could try a lower psi relief spring. Easy enough to swap in a few minutes.
I think a standard pressure for a melling is 45psi.
 
Maybe a bit high. It must be high pressure pump and nit high volum.

high volume numbers on my last MP pump were around 65 hot cruising
 
yes i agree, bearings are defiantly getting oiled. much better then 'not enough' oil pressure. i thought the relief valve may not be working correctly. Suppose i could pop it out and give it an inspection. i thought it's job was to limit the overall PSI as a bypass. Maybe i'm not understanding the actual function of the relief valve??

come to think about it.... i bought that pump 2 marriages ago. I'm suspecting it's a High Pressure and not HV...

i'm going to crawl under it and see if i can see the numbers.

i'm glad i asked , makes me feel better about it.
i appreciate everyone's responses!!!
 
Last edited:
It’s too high for me, no need for 80-90 psi. Switch to a standard pump.

This part should be first: What do you do with this engine, what is the highest rpm you rev it to?
 
Those numbers are very close to where mine have been for years. If I did anything at all, I would switch oil viscosity to 10w30. Roll with it my Friend!!!
 
Last edited:
"Verify with a mechanical gauge."

-- this i did do . i neglected to mention it.
 
Milodon makes an externally adjustable plug for the end of the relief spring. Dial in (with a wrench, duh) whatever cruising pressure you want. (I actually had one too high once, well over 100psi cold, that blew the filter into pieces.)
 
High volume pumps have taller pump gears. High pressure pumps just have a stiffer, or shimmed stiffer, relief spring.
HV/HP pumps have both.
Edit: I like to see 75lbs in the lights at 125, but 60 at frwy speeds is enough.
 
I believe 7 psi per 1,000 rpm is all that’s needed. My street/strip 440 has lived 20+ years with a high volume pump, 7 quart oil pan, and Hemi full groove bearings at higher pressures very similar to the OP. I also have a 175 shot of nitrous on tap that gets used.
 
Last edited:
Post 8 - did this having desired result. Was running 20/50 though.
 
33 IMP said:
Milodon makes an externally adjustable plug for the end of the relief spring. Dial in (with a wrench, duh) whatever cruising pressure you want. (I actually had one too high once, well over 100psi cold, that blew the filter into pieces.)
Click to expand...
i saw 440 source offers one too. I wonder if they source them from Milodon. i'll see if i can find a p/n, might be cheapest option just to lower it a scooch

or next oil change get 10w30 like post 8 suggested...

or just be happy with it. 1500 miles since , no blown filter (yet)
 
R413 said:
It’s too high for me, no need for 80-90 psi. Switch to a standard pump.

This part should be first: What do you do with this engine, what is the highest rpm you rev it to?
Click to expand...
WHY?? what is the controversy??? Its better to have more oil volume (at adequate pressure) available than needed as the bearings are cooled and the crank is supported by the hydrodynamic oil wedge as the crank rotates. Pressure is a function of bearing clearances, oil viscosity and delivered volume. Perhaps you would like to go back to the days of the GM 235 inch 6 cyl. engines using a dipper on the bottom of the connecting rod cap.....now begins the controversy of which oil is "best" and which brand is "best"... "what I use is better than what you use"......my beer is better than your beer.....or scotch or bourbon or gin or...???......just my opinion of course.....BTW. I use Mobil One. 10W-30 with a high VOLUME pump @ 6 qts + 1 pint of ZDDP....
BOB RENTON
 
and Bob,
i like bud light lately ... dont know why (JK)

1683754071665.png
 
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