225-231 Flywheel ID

How do you know what you are looking at when looking at a man trans flywheel? Are there casting numbers peculiar to the 225 or 231? Is there a drill hole balance pattern specific to one or the other? What are the specs for balancing when changing a 225 to 231 or 231 to 225? If it is a heavy, say 40#-50# 10.5" flywheel is it automaticly a 225 jeep version. It would be nice if some expert would put this info in the tech library. Do you have a flywheel laying around, how much does it weigh, what are the casting numbers, the disk size, balance added or subtracted and where in relation to the pin or clocking?

 

Here is the bolt pattern for a buick v6.
The flywheels do not weigh more than 70lbs, I think mine was 64-68lbs when I had it surfaced, can't remember for sure, I personally have never seen a flywheel for a Buick v6 that was lighter than about 40-45lbs. An engine shop will know the engine balance for an oddfire compared to an evenfire motor. I do remember seeing the difference on the web once but can't remember where.

 

McLeod steel flywheel 77-87 231 V6 even fire PN. 467100-6A
1964-87 225, 231, 300" V6 odd fire PN. 465200-5C Summit Racing Equipment. $$$