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If you're concerned about oil flow to your bearings, you should install oil pressure and and oil temperature gauges to measure how much pressure is being developed by your oil pump and how hot your oil runs.  If your engine is in good condition and its oil pressure at fully warm idle is within the manufacturer's specifications, your oil pump should have enough capacity at higher engine speeds.  At higher engine speeds, you should see your oil pressure top-out at the rating of the pressure relief valve.

Hydrodynamic oil friction from higher engine speeds and/or loads generates more heat in the engine oil.  Heat is rejected from the engine oil mainly via the oil pan and the oil filter.  Higher oil temperatures will cause the engine oil to become less viscous and therefore its oil pressure will decrease with increasing temperature. Unless your oil runs really hot, you probably don't need much more than a 30-grade oil (0W-30, 5W-30, 10W-30).  Due to fluid friction, with the same engine load and speed, less viscous (thinner) oils tend to run cooler.

If your engine is in good condition but your engine oil pressure tends to be low due to high oil temperature, you can either increase the pressure by switching to a more viscous (heavier) oil (eg, change from 30-grade to 40-grade), upgrading to a higher volume pump, or adding an engine oil cooler. Using a heavier oil gives the added benefit of getting an oil with a higher HTHS (High Temperature, High Shear) rating for thicker oil wedge.  An oil with a higher HTHS rating will tend to have greater friction and therefore lower fuel economy.  Compared with mineral oils, synthetic oils should also have higher HTHS ratings due to their reduced reliance on Viscosity Index Improver additives.  Higher volume pumps and/or higher viscosity oils place a higher load on the oil pump's drive gear, which can lead to gear failure so be sure that this is a recommended option for your engine.  See SL6 Oil Pump Gear Failure and Oil System Information.

If your oil pressure is within the normal range but you want more flow to your bearings, you would be better off switching the safety relief valve spring to a higher rating than switching to a high volume oil pump. A higher oil pressure relief setting will reduce the amount of oil recirculated back to the sump.  However, this change places additional load on the oil pump so be sure that this is a recommended option for your engine.

The Mopar rule of thumb is 50 psi up to 5000 RPM and then 10 psi for every 1000 RPM increment (ie, 6000 RPM requires 60 psi).  For Chrysler products, a simple oil pressure upgrade is to replace the OEM relief valve spring (45-55 psi) with the 75 psi Hemi Oil spring (PN 2406677) in slant six and B-RB big block engines.  Small block LA engines use the 75 psi (PN P3690944) spring.  With my slant six with the original oil pump and a hemi oil spring running 10W-30 HDEO, I get 70-75 psi at ~2500 RPM on the highway during the hottest summer days here in Ontario.