Have one that spun a rod bearing. Won't clean up for mopar size bearings. Anyone turn one down to 2.0 and use a chevy spec 6.0 rod and pistons?

Id think it might be less costly just to buy another 4.00 crank in good condition (new) id never buy parts around a cast crank.

But im sure you could make it work, but why?

Inexpensive rod and piston choices- some even with 1/16 1/16 3/16 rings.

I hate to waste something that could be made to work. I am just not wired to throw stuff away.

Do you know the clearance you had on the rods and mains? I `m assembling a SCAT cast 4.0 presently and have .0015 on the rods and .0018 mains with the King bearings that came with the assembly.Which I feel to too tight for 6000-6500rpm . I would like to have over ..002 on both , therefore going to try a polish and federal bearings{ supposedly kings are tighter } in hopes of getting a little more clearance.

Sorry I don't I bought the engine with the rod bearing already bad. You may be able to find some .001 oversize bearings, or if you have some old stock bearings on hand measure them and see what you come up with. Polishing as you mentioned would work but it would take a while to get there.

Time for a re-wire.
You want to spin it to 6500 ?
How much is a new cast crank ?
Forged is around 750.
How much to turn .125 off of the remaining journals ?
Cheaper to offset grind and add stroke I bet , but even after grinding and indexing , you will be into it for more than the 400.00 a cast crank would cost.