Which kit work better for the g35 the stillen x double exhaust or the injen h double exhaust? I know there is price difference. which one will give more hp? Would it make more noise?

 

exhausts dont make noise. engines do.

 

Get the HKS.

 

Stillen will give you more hp it sounds like stock just louder and deeper... Injen just sounds mean as hell but the Drone sucks... a few members got rid of thier Injen Exhaust a week after installing it because the drone was that bad.