The Ford Barn - View Single Post - The Terry Burtz 5 main bearing engine blocks are back on track.

Terry Burtz, Calif · 04-06-2021, 06:45 PM

The old "basic rule" was that 10 psi of oil pressure was needed for every 1000 RPM.

Under the old rule, you should have 25 psi for 2500 RPM.

The basic rule is no longer applicable with modern metallurgy and lubricants.

One thing that may have helped the low oil pressure problem is that the "New Engine" connecting rod journals are cross-drilled and this provides 2 places where oil can enter the bearing ensuring an adequate supply of oil.

During the 1st day of engineering evaluation testing of the "New Engine", we used cheap semi-synthetic motor oil, ran it for 6 hours at 3100 RPM (75 MPH), had 4 psi oil pressure because of an open 5/16 inch diameter hole venting the main oil galley, had an average water temperature of 190 degrees F, and had an average oil temperature of 263 degrees F. On the 2nd day of testing at a more realistic speed of 2100 RPM, we again had 4 psi oil pressure, had an average water temperature of 168 degrees F, once had an accidental head temperature at the spot where we were measuring water temperature of 260 degrees F when we inadvertently ran it out of water, and an average oil temperature of 180 degrees F. On the 3rd day of testing, the engine was in a car and climbed Overlook Mountain that is west of Boulder CO. A chart of the test data can be found in the September 2020 update.

04-06-2021, 06:45 PM	#307
Terry Burtz, Calif Senior Member Join Date: May 2010 Location: Campbell,CA, USA Posts: 319	Re: The Terry Burtz 5 main bearing engine blocks are back on track. The old "basic rule" was that 10 psi of oil pressure was needed for every 1000 RPM. Under the old rule, you should have 25 psi for 2500 RPM. The basic rule is no longer applicable with modern metallurgy and lubricants. One thing that may have helped the low oil pressure problem is that the "New Engine" connecting rod journals are cross-drilled and this provides 2 places where oil can enter the bearing ensuring an adequate supply of oil. During the 1st day of engineering evaluation testing of the "New Engine", we used cheap semi-synthetic motor oil, ran it for 6 hours at 3100 RPM (75 MPH), had 4 psi oil pressure because of an open 5/16 inch diameter hole venting the main oil galley, had an average water temperature of 190 degrees F, and had an average oil temperature of 263 degrees F. On the 2nd day of testing at a more realistic speed of 2100 RPM, we again had 4 psi oil pressure, had an average water temperature of 168 degrees F, once had an accidental head temperature at the spot where we were measuring water temperature of 260 degrees F when we inadvertently ran it out of water, and an average oil temperature of 180 degrees F. On the 3rd day of testing, the engine was in a car and climbed Overlook Mountain that is west of Boulder CO. A chart of the test data can be found in the September 2020 update.