Twin Tec Ignition Module for 1999-2003 Carburated Twin CamTwinTec High Output TC99 06 XL04 06 The Twin Tec TC88 module offers easy plug in installation. All the switches are accessible from the top a significant advantage for most installations. Five rotary switches are used to set the operating modes, adjust the initial timing and timing advance, and select the RPM limit. Since the TC88 engine uses a non adjustable crankshaft position sensor, mechanical timing adjustments are no longer possible. The TC88