The biggest Crome power adder is the valve cover. The second biggest are side plates. An "all out racetrack only" engine would have a fuel pump block off plate also. At that point the car would have to be trailered because of such poor street maners. Seriously, I did read a article where a 2bbl 350 totally stock was dynoed at different stages of build. The thing that held the engine back the most was the stock air cleaner, I would think this would apply to any stock six be it Chevy or ford or any make. IIRC the air cleaner helped almost as much as headers! Jay6155
