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Got yet another issue with my Aerovee (S/N No. 350). This past weekend, started the engine for the first time. Had an issue with the timing (another topic here on the site - working thru this), but noticed that when the engine was running, the oil pressure hung around 15.7 to 16 psi. No higher, no lower. Saw a post about the back oil pressure relief valve and installing a shim under the spring. Tried this, but still have 15.7 or so psi on the oil pressure. I am monitoring via the MGL Discovery Lite. All wiring appears to be in order. Any other builders see anything along these lines and if so, how did you resolve and get the pressure to where it should be? the specifications state that 10 psi is the minimum(hot oil, idle RPM). I think I should see a little better - close to 45 or so. Have not run at any RPM of 2500 or better. Just enough to figure out timing and mixture...
Thanks for the help and ideas.

Make sure you have your MGL properly programmed for the sending unit you have. Verify with a mechanical gauge if necessary, as sometimes the settings on the electronic panels can drive you nuts.

Does anybody have a millennial they can rent me for a weekend to go thru these new fangled instrument panels? Sometimes I miss steam gages. Thanks for the tip Joe. I'll be scheduling time with you soon for transition training.

From 1 hour through 150 hours, and a couple of re-builds, I see 32-35 psi during flight. Never any higher. About 20 psi at a very low idle on the ground, and just over 20 psi at normal taxi speeds. As Joe noted, try a mechanical gauge so you have a true base-line to make sure the EFIS is actually reading correctly. Make sure the RDAC (brains of the EFIS) is grounded to the engine block and not the air frame.

I'm on my 3rd oil pressure sender (VDO to MGL enigma) I have never found it to be accurate. I installed a mechanical gauge at about 60 hours (300 hours ago) and always monitor that. I see 50 psi at cruise and about 25 to 30 taxiing in after a flight at idle. initial idle with the oil only at 100 degrees it is still 50 psi. If the pressure truly is that low you can use an adjustable plug in the rear plunger. It replaces the standard plug and eliminates the shims under the spring. You can adjust the spring tension without removing the plug and loosing oil. They are only a few dollars from Great plains and several "Bug" suppliers on the internet.

btw: In RV land they almost always install the oil pressure sensor on the firewall, with a restrictor fitting and hose to the sensor. Supposedly because vibration from mounting on the engine would cause inaccurate readings. (fwiw - not sure if relevant but in case it is useful)