i have an 81 f-100 with a 302, when i first start the truck the pressure is up about 40, but when it warms up it drops to anywhere between 10-20 psi. while driving it stays around 25-30 psi

 

that is liveable, how many miles on the engine?

 

93k that i know of

 

a little low but that is an old engine. i get 70 at start up, and 50 cruise for the first twenty or so minutes, then it is around 35-40 or so. I jsut installed a new oil pump too so that is why i got those numbers

ken

 

10-20 psi at idle is more than enough.