I am rebuilding a 67 318 with a small Comp hyd. cam. I am using the stock rockers over. The block/heads were milled a total of .050 and Comp cams has a .050 shorter pushrod (part number 7956-16) but it is a hollow smallblock chevy type. The lifters are also oil through.

Will there be an oil pressure problem with the oil coming up through the pushrod and out the oil hole in the rocker arm cup? Both Comp and Mancini list the same pushrod for this application but they give no details. Anybody here have any experience with this application?

Shouldn't be a problem. Stock 318's came with hollow pushrods.

My 318 ones were not hollow. If the lifters oil thru the top(most do) with hollow pushrods that would loose too much pressure & a non magnum valve train gets all it needs from the passage from the cam on each side.

Run the oil pump with the intake off. Not much oil bleeds out of the top of those lifters. I don't think its going to be a problem.

You'll probably lose a little pressure, but ya also gotta think about the strength in solid versus hollow push rods. I had a 318 2 bbl that had them, never had an oil pressure problem but did break some spinning it out in the rain and taching it up. Dumb kids.