My latest quandary with my engine is ballooning oil filters. As soon as the engine fires it pegs the oil pressure gauge and shoots oil out of the top of the filter after it’s been pushed away from the block. I replaced the oil filter adapter thinking it was the baffle inside of it, but it just blew the third filter. I got the engine from a friend of friend so I don’t know the particulars such as bearing clearance. It has a high volume pump that appears to be brand new, but as I’ve found, new doesn’t always mean good.
L.D.
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The problem is likely a stuck oil pressure relief valve. While it is possible to remove the pressure relief valve and spring and perhaps clean it to allow it to work, if the piston is truly stuck, it might be better to invest in a new oil pump.
If you replace the pump, do so with a standard volume and standard pressure pump.
Assuming the engine has standard bearing clearances, it’s not necessary to run either a high volume or a high pressure pump. Tens of millions of small blocks have been built without stock volume and pressure and they have been running for more miles than anyone can count.

The Relationship Between Oil Pressure & Oil Volume
The concept of oil pressure and volume are directly related. It’s too difficult to check for volume of oil delivery, so instead we use pressure as an indicator of volume of oil to the bearings. So, when we see pressure we know that a volume of oil is being delivered to the engine.
Unfortunately, too many enthusiasts believe that more pressure is better. That is not always the case.
Let’s look at oil pressure at idle. Many are not comfortable with less than 30 psi at idle. I’m not sure why this is. Do you know how much hp it takes for an engine to run at idle? Generally it is slightly more than what it takes to overcome internal friction in the engine.
This means maybe 2 hp and perhaps less. So lubrication requirements for oil to the engine should also be minimal. If we take the old adage of 10 psi per 1,000 rpm to heart, then all you would need is around 10 psi. This would actually be acceptable but most gearheads freak out with this low a pressure.
The extension of that 10 psi per 1,000 rpm edict is that at 6,000 rpm, we would at least 60 psi. This is certainly acceptable but not necessarily a set-in-stone requirement. We suffered an oil pump pickup failure on my 420ci small-block during an open road race where the engine ran for over one hour at 6,000 rpm with less than 40 psi of oil pressure. An after-race inspection to replace the broken pickup revealed the bearings looked perfect. Then engine was making over 550 hp and we were using synthetic oil which certainly helped with lubrication.
Mild performance engines running over 60 psi of oil pressure generally are merely wasting horsepower driving an oil pump at those higher pressures. We found by reducing oil pressure with lighter oil that that we could improve horsepower 2 to 3 numbers. Lighter viscosity was an easy way to reduce the oil pressure slightly. We don’t recommend arbitrarily reducing viscosity unless you track internal engine wear with precise used oil analysis.
The point is that there are small power gains to be had by managing the pressure and volume. It’s something worth thinking about.
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