Hi, i did change my engine lest fall. I had problems with my head one valve was not adjustable anymore so i bought that engine rebuilt from Datsunparts LLC think that was a mistake. The thing is burning oil and i got uneven oil pressure. It runs great pulls hard but burns oil and scarry uneven oil pressure. my other engine use to be dead center on the oil pressure gauge this one goes up and down. and i cannot figure the  patern. It is not linked with reving it can be high at low rev and low at h