Automotive acoustic is living a revolution due to new power train introduction. Interior car noise is now designed, offering fresh perspective in terms of sound ambiance. For 4-cylinders car, interior car noise can sound more expressive in order to increase sensation by motor organic modification. Our goal is indeed to conceive interior car sound which is well fitted with car dynamic. This experience studies the relation between acoustic perception and motion perception in a dynamic driving simulator. We test motor noise influence on the car perceived power during an acceleration by modifying motor noise loudness and brigthness. Subjects sit in passenger side three different accelerations are reproduced in the driving simulator. We show that car perceived power increased with loudness whereas brightness doesn’t have an impact.