Oil pressure, how much is too much

[mopar 3 B]

Don't worry about the pressure. Just stay away from cheap 80 psi gauges.

 

[oldkimmer]

The old S/SS car I bought would wrap the needle past 100 cold. 75 warm idle. 100 down the track. It wore the bushing and shaft about every 150 runs. No problem other than that. Mim

 

[RJRENTON]

B

The old S/SS car I bought would wrap the needle past 100 cold. 75 warm idle. 100 down the track. It wore the bushing and shaft about every 150 runs. No problem other than that. Mim

Better too much oil pressure than not.....oil pressure is cheaper than bearing replacement. The GTX HIGH VOLUME PUMP AND 10W-30 MOBIL1: Cold=80 psi; hot @1200rpm=60 psi; hot @ 4000rpm=75 psi. Zero wear on distributor bushing or gear.
BOB RENTON

 

[mopar 3 B]

If there is distributor gear and bushing wear. Just maybe the wrong metal types are being used.
Let's also not confuse volume with pressure.
I look at it this way. That big oil pump and it higher pressure is worthless without the right bearings.

 

[RJRENTON]

If there is distributor gear and bushing wear. Just maybe the wrong metal types are being used.
Let's also not confuse volume with pressure.
I look at it this way. That big oil pump and it higher pressure is worthless without the right bearings.

I'm totally aware of the differences between the volume and pressure relationship and I want a HIGH VOLUME PUMP.
On my RS23V0A****** '70 GTX, the bearing's are: Clevite tri metal (steel backed Babbitt with copper tin overlay) mains, full groove upper and lower @ 0.0025" mains to provide 360° degree rod bearing oiling and Clevite 77 rod bearings @ 0.0025" with ARP HARDWARE holding it all together.....and its been this way for 25 years. I tighten the main cap bolts 20 lb/ft more torque for better bearing crush and to prevent turning. Just my way of doing it......
BOB RENTON

 

[33 IMP]

When the oil filter blows off the motor on a cold start, that's probably too much. (Been there, done that).

 

[RJRENTON]

When the oil filter blows off the motor on a cold start, that's probably too much. (Been there, done that).

The high pressure relief valve in the oil pump limits the nax pressure developed snd the burst rating of the filter prevents this from occurring plus I use WIX FILTERS # 51515R
BOB RENTON

 

[33 IMP]

The high pressure relief valve in the oil pump limits the nax pressure developed snd the burst rating of the filter prevents this from occurring plus I use WIX FILTERS # 51515R
BOB RENTON

.... unless you are attempting to boost warm oil pressure, with an adjustable pressure relief valve....
and miss really bad on the adjustment......
and hadn't yet learned not to use Fram filters.
( I seriously pegged a 100 lb mechanical gauge, my guess? 130 lb)

 

[RJRENTON]

.... unless you are attempting to boost warm oil pressure, with an adjustable pressure relief valve....
and miss really bad on the adjustment......
and hadn't yet learned not to use Fram filters.
( I seriously pegged a 100 lb mechanical gauge, my guess? 130 lb)

I WOULD NOT use an adjustable high pressure relief valve in the oil pump. It is a standard MELLINGS/Mopar high volume pump with the relief valve spring for that specific application WITHOUT any shims to achieve my results. My operating specs are determined by bearing clearances and oil viscosity. IF you are proponent or understand the concept of the HYDRODYNAMIC WEDGE LUBRICATION THEORY of journal bearing, a higher volume of oil promotes better bearing cooling and allows better film strength at the boundary layer interface.
Maybe the following will help you understand:
hydrodynamic journal bearings, the shaft rides on a thin film of oil, which separates the shaft from the Babbitt bearing surface. The clearance between the shaft and the bearing bore, the bearing load and the shaft speed determine the thickness of this film.When the shaft first begins to turn at slow speeds, there is very little lubricant between the shaft and bearing. This is known as the boundary lubrication regime. During this period, the asperities, or microscopic imperfections, on the shaft surface come into contact. Nearly all of the wear that occurs in journal bearings happens during boundary lubrication. In this condition, the bearing is vulnerable to damage from contaminants such as dirt or ash that may be larger than the oil film.As the shaft speed increases, the oil film forms between the two surfaces. At first, the film is thin enough that the asperities still come into contact, which is known as the mixed film lubrication regime. Once the film is thick enough to fully separate the surfaces, it is known as the full film lubrication regime. During this regime, there is no wear of the shaft or bearing, and the bearing is generally safe from contaminants smaller than the oil film.
BOB RENTON

 

[mopar 3 B]

I use nothing but 50wt racing oil and have never had a psi reading over 95.
Not sure why one would even want it.