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.

The Hybrid TMS features dual outlets for full recirculation, 50/50, or full atmosphere venting. Configured with the supplied plugs for 3-stage sound control.