The exhaust is custom 2inch straight through with a 3 inch back box (im not sure on the back box make), and the Manifold is a 4-1 Hotshots manifold, which from what i understand is as rare as unicorn farts, im sure some of the guys on here would know more about it than me i think it improves flow and in my opinion made the throttle response tighter, i could be imagining it but it feels like it to me