[gmc684x4]

If your building high hp race engine then yes

And untill you tear apart your current build you wont fully know yhe crank specs
Is your oil pressure still good ?

Current crank can probably just need a polish

Alternatively you can just replace the crank

I have built 300 hp engine with a 20 20 crank no issues

Are you wanting a roller cam best solution is go with a 86 up block
An l31 block is the 86 up fitted with roller cam and vortec heads

Good cheap canadates i found are full size vans ran l31 until 2002 can be found cheap with clamed failed head gaskets as the factory gm intake gaskets always leak

I picked one up free that way po was determined blown head gaskets towed it home fired it up drove into the shop 40 psi oil pressure shut off
Pop the hood watch the coolant run down the front of the block check oil yes it is milky i know he did not wash the bearings out that would affect the oil pressure on a stock motor