400 block clearancing

Anyone happen to have any pics of the before/after clearancing needed to install a 4.25 crank in a 400 block. Mainly curious as to how much has to be removed around the oil pickup tube location to see how much material is left to be able to use an internal pickup.

Depends on which rods you use. If you use a 2.200 rod journal and a high quality rod like an Oliver then you might not need to clearance much at all.

With the steel H beam BB Chevy type rod it ain't much, .060 to maybe .120 on a slope up high on the boss

Looking at the 440 source 400-512 kit at the moment. Comes with the 2.200 rod journals.

This might give ya a bit of an idea.

400 block with Molnar 4.250 crank and rods.

440 source 400/4.250

2

The clearancing is a small amount on the pickup tube boss and that is all. It’s a piece of cake.
I also ran a 1/2 pickup tube. Had to grind the tube just a bit so I don’t recommend a 1/2 pickup
If you’re not gonna rev it that high.