I have a 97z M6, which is better, the 10 or 12-bolt?

 

A 12-bolt is going to last longer if you run drag radials or slicks because it is stronger. The only downside is that it eats up more horsepower than a 10-bolt.

 

there are many variations to the 10 bolt, the 7.5 inch which comes in 3rd and 4th gen camaros is known to be a bit weak i guess, mine is still holding fine but others have had problems launching with sticky tires.... the 12 bolt is a good choice and built right can take just about anything you can throw at it, expect to spend about 2500 seting a 12 bolt up for a 4th gen