Like Cab said 65 or 66 jets in center carb and this big engine likes fuel and respond to it so go up 2 to 4 steps on the sqirter on center carb ! You will feel the differens. On the outer carbs i ended up with 82-84 jets so i gues Cab reved his engine more than i did. If you realy whant to have fun with the six pack set up look for the mecanikal carbs that whas sold thru Direct Connetion whit list number 82&83 or if you can find the BG carbs that i run now that respond way better !