I have an original 371 rebuilt engine including a rebuilt oil pump. My oil pressure appears to be low. What should I expect at idle and in normal operating range?

 

My machinist told me 10 lbs per 1000rpm is OK. So at idle you may drop down. I would worry a little about readings below 20 at low rpm but 40 is pretty normal on the road. When we first built my hopped up J2 I ran a stiffer popoff spring in the pump and had 55 lbs but Jim said we needed a cushion of oil rather than a blast and had me reduce it to stock which is around 40 This engine has run well for 20 years all over the US and some of Canada. Pat