A lot of riders have already invested in performance upgrades for their stock engine by the time they are ready to move up to a complete big inch engine. Wouldn't it be nice to be able to save some money by using some of those items on your new engine? Well now you can! S&S is offering T-Series engines for 1999-2006 big twins without fuel or ignition systems. So if you have already added a performance carburetor or an EFI throttle body and tuner to your stock engine, you can use it on your new engine. A carb or throttle body that fits a stock engine will fit the new S&S engine because the heads are specially machined to compensate for the increased cylinder length so a stock length manifold will fit.