Quote Originally Posted by Patterson View Post
I guess quality comes into play with extentions, if you upgrade to a grade 8 bolts and lock tight, you should never have trouble if installed and maintained correctly. I myself have pushed them with 250hp running 8's 1/4mi but I would not go over anymore that that. A true arm is a better way to go but some have to work with what's laying around
I've seen stock 600's break good quality ones. Just luck of the draw mostly I suppose.