it's my understanding a 225 has cast iron sleeves, (some guys call them steel bore) and the 260 has aluminum sleeve with a nicom coating applied to the bore.
If you throw enough coin at it and do it correctly, a 225 pro max will make over 300hp easy. You'll see one at Barefoot Bob's this weekend Matt, running on an Ally SS2000 with Dave Hanle doing the piloting.
