I put a set of the Headman shorties on my Son's 72 Dart 4 door with 360, bored 30 over, one of the members on here gave him a set of 202 valves for the heads, heads were ported and polished and shaved 50 thousandths. The only issue with the headers, the muffler shop says the A bodies are hard to get the pipe fitment. All that to say this, the shorties perform very well, the car is a beast. He is having the time of his life spanking many local cars.