TheForce steps up to 2" and has no core unless you buy an optional Quiet core and who the hell would do that when that is all that pipe is about - mid to top end power beating all the rest - The less the bends angles the better the flow - WB (23 discs on the WB will give you the most power) and Jardine have the least radical and same length, and if you add a D&D can - the power becomes Force like in its delivery rush in mid and top, though the Force still has it on the top - it is steped - they both beet the Force on the bottom on regular take off, but launch that puppy at 3g's and your golden - the D&D and Pro-series are steped & shaped almost identical except the D&D's last step is 4" longer than the Pro-series which splits to two there - the Bub is just a reverse cone desogn with a built in spark aresstor( same as the D&D can in interior design thought just different shaped outer shell) and all about bottom end - still beats the V&H in torque and equals it in power. My custom header designed for TP's LSR is the bomb with the early S2 2" inlet Suppertrap with all 12 discs - great bottom, middle and top end - gave it to me when he upped his engine size cc's to 720cc - everything goes quiet rappedly now - lol
EZ
