the right heads!

W2's or W5's are not really "street friendly" heads. I'm pretty sure only TTI makes headers that fit the W2's and W5's will most likely have to be custom made. Next up is intake availibility. Then humungo port size.

Stick with your J's, you will be much happier in the long run and on the street. Iron heads will make more power everything else being equal too.

The general rule of thumb is that each cfm of head flow will support a bit more than 2 hp. For example, let's say that your heads flow 230 cfm at .500 lift. This should support around 480 hp. W2's flow around 260 cfm at .600 lift. Do you really want to run .600 lift cam on the street?