What crank pulley is run with that balancer to align with basic fan and alternator arrangement?
I am debating whether to go that size or go the smaller and run the OEM depth crank pulley.
I bought the 3-ring unit because that's what ATI recommended for the rowdy 499" its going on.
The 3-ring is .370" longer than the 2-ring that everything stock is supposedly suppose to align like factory with.
Obviously the 3-ring provides more torsional damping than a 2-ring can provide, so depending on your intended use, stroke, and rpm range you'll need to decide.
That said even a 2-ring ATI is going to do a much better job damping than an OEM stock unit ever did when new.
If you use a 3-ring you just need to make .370" thick spacers for the alternator, water pump, and/ or whatever else you're using a pulley on.