July 24, 2006Bamalam
This 2-1/8"ID x 2-1/8"OD coupler that fits inside exhaust pipe, shifted the torque range giving me better mid to low end torque. With out out it the torque is in the mid to high end.
Better for stop and go driving or drag racing. If I were going to race on an ovel or slalom track the I would remove the coupler.