There is a lot of good advice here. I suggest you run the thicker oil (maybe even straight 40W or 50W)....while you're finding and/or building another small block. You can get a used 318 pretty cheap or find a 340/360 & build it a little if you have more cash. I would guess you'd gain about 10psi of oil pressure with 40W or 50W oil.
70 Roadrunner convt. street car
440+6, NOS, 4-spd, SS springs
'96 Mustang GT convt. street car
'04 4.6 SOHC, NOS, auto, lowered
"Officer, that button is for short on-ramps"
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