The straight out cover 24 # adopts T304 stainless steel suction head, which is suitable for some high horsepower vehicles that the original factory does not pay much attention to torque assistance or some racing cars that mainly focus on high revs. The common car models on the market, due to their small displacement, often use low revs. When two columns of sound waves overlap, they interfere and cancel each other out, reducing the sound intensity and thus achieving a soundproofing effect. So the vast majority of people choose back pressure exhaust as the better option.
