Spec II is a specially designed system for competition use only. Its simple straight thru design creates an increase of exhaust gas velocity in order to improve efficiency. The middle silencer (resonator) on the main pipe is designed to maintain torque in the low to mid speed range.
This straight pipe is very nice. I bought 1 myself for me 85 Corolla and it sounds really nice also. I don\'t use the silencer as much but besides that everythings nice. I\'m 15 right now and I\'m trying to get somewhere with my 85 Corolla that me dad loaned to me. They straight pipe I bought just killed it. Its really awesome!