Swapping cranks

[one90gt]

Wanted some oppinions from people here...

I've been helping a freind swap the crank out of a 306 that had the snout threads/keyway chewed up from a blower pully (everything is about 800 miles old from being freshened up and looks new). I have a stock crank from a short block I parted a while back. The 306 has new pistons ect but still has a stock crank . If the crank is the exact same size where the rods connect and the other places it rides in bearings can I just swap the good one for the bad or will I need to get all new bearings, ect and have it all ballanced again?
If it makes a difference this moter will be pushing about 8-12 lbs via an S-trim w/ AFR185's, a blower cam and about 9 to 1 compression.
Thanks for any input.

[mustangboy]

I think I would just use it as an opportunity to put a decent aftermarket crank in it. :)

[NXcoupe]

Yes, you would need to get it balanced for the new pistons, especially in a hp application like yours. If it's a stock block, the crank will outlast the block usually. You also need to mic the crank and make sure it is the same sizing as the original, and it is silly for the price of bearings to reuse used ones, even if they have low miles.

[408gt91]

Yes, you would need to get it balanced for the new pistons, especially in a hp application like yours. If it's a stock block, the crank will outlast the block usually. You also need to mic the crank and make sure it is the same sizing as the original, and it is silly for the price of bearings to reuse used ones, even if they have low miles.

+1 it would be crazy not to balance,and use fresh bearings.