On my 85 B2, 2.8, the factory gauge will barely move off the peg after warm-up and I've driven it for over 8 years and it still runs okay. I had the engine rebuilt after the person I bought it from had ran it dry on oil. I don't know what all the rebuilder did but whatever it was, sans the oil pressure, it does okay. I figured when it breaks I will fix, or have it fixed.