I used to have a DC sport header but I got rid of that when I thought I was going to go turbo. Now that I am not going turbo I have my old DX header on my D15b7. This thing is ugly and looks like it can't be flowing too much better than say, a VX manifold. My friend gave me his old Z6 manifold and I was thinking about tossing it on. But it doesn't really look that pretty either. I don't plan on spending money on my 16 second NA civic, but while I am saving for my turbo project I was wondering if I would even notice any difference with the Z6/EX header as compared to mine. It looks like it flows maybe a little better but the DX header looks like it has bigger primaries (it only has primaries, no secondaries) So, finally, what I am looking for is people that switched from a stock DX to EX exhaust manifold to tell me if it is worth it. I don't feel like getting on my back for 2 horsepower. Sorry for the long post.

 

dont change it man
pointless

 

if you modify the collector on the z6 exhaust manifold to flow a little better (they are two layered.. remove the inner layer), it will most certaintly flow better than the 4-1 DX manifold. However, the z6 manifold has its problems with the runners being very small at the top.