The latest Smartstream 1.6 T-GDi engines fitted to Hyundai's i20 N and other models do not use a MAF sensor which means that you can vent to atmosphere for that blow-off sound, if you like, without causing any driveability issues or 'Check Engine' lights. This Deceptor Pro 2 TMS valve features dual-outlets with a full bias adjustment system that allows you to control the venting bias to your taste immediately and directly from the driver's seat.