I finally have the rebuilt engine back in the car. It starts right up, idles fine, but dies immediately if you touch the accelerator and then let it come back to idle. I can raise the rpms to any reasonable speed and hold it there, but within 30-45 seconds it seems to try and lock up. It takes more and more accelerator pressure to keep the rpms up. The engine finally dies and if I immediately try and restart - the engine is very difficult to crank - like it's under a load. If I wait a minute or two it starts right up with the same symptoms. I don't know if this is a lack of oil issue causing it to start to lock up or something else. At idle the oil pressure is about 10 - 15 psi on the factory gauge.