ill throw on my stock airbox and see if I can feel the difference since I did the cool head the butt dyno says it accelerates a lot faster, pulls harder and has a lot more traction that's for damn sure but some of that is due to the -2 swinger. I'm cutting the tubes down about an inch and a half so that I can bolt it in. Since the manifolds spaced the carbs so much further back the bracket doesn't fit so I took it off and now it fits perfect so I'll be cutting a good portion of the tubes off. If it is losing power it'd probably be bc it's working harder to individually pull air through individual small filters instead of one big one with a lot more space inside it like with the big filter. Or could also be that the guy that did the dyno had the jetting off who knows. I'll keep you guys updated. I won't be dynoing mine since I'm not going for the numbers just something that works great for what I mostly ride it as long as I've got that brown ring around the spark plug I'm happy.