torque converter balancing

Just took my coan converter to my trans guy while he is rebuilding my 904 and I got a surprise. The balanced converter I bought for my 360 doesnt match the stock converter coming out which does not have a balance weight. Can a 360 be internally balanced by using a 340 crank? The damper isnt a big unit, so how can this be balanced? Thanks.

stock converter should have weights on it for externally balanced 360

Yes..a 360 can be internally balanced...but a 340 crank will not fit it since they have different main bearing size.,,,mallory metal will need to be added to the 360 crank...

If the coan converter has no weights on it...USE the B&M flexplate for a 360/904 combo....