Quote Originally Posted by DennyW
The 66 is different than 67 and later. They are pretty beefy though. Get a shift kit, a beefy band, and smaller end steels so you can add a couple more clutches. It should hold 500 hp. Check a couple places like TCI for beefy parts to add.
so it's mainly that the casing isn't as rigid as the newer years?
I was indeed thinking of putting in some thinner end steels and add some clutches.