Oil pressure at idle

[jdhcth]

I have a 283 that I just rebuilt and put all new goods in it, oil pump included. At idle I'm gettin' about 20PSI. This seems low to me. At cruising speeds it runs in the high 40s. Does anyone know what ranges I should be seeing. I know I'm runnin' high RPMs on the freeway, 3 speed Saginaw with (at my estimate) a 3.73 gearing.

Speaking of gearing, In 3rd at 65 I'm doing about 3200 RPMs. I have 31" tires. I did the one tire rotation and marked the driveshaft. Came up like 3.73. With stock diameter tires wouldn't this be in the 4s? Say 4.11 or so?

Thanks,
JD