I ran my 426 to 7300 regularly. As mentioned before, stock shafts and rockers. I just don't understand the gripes in how expensive these engines are to build. A custom piston, for instance, cost pretty much the same across the board. Compare the costs of the gen 3 Apache or Big Gas head to that of a W series or Eddy Victor. Then work needed for each to flow, say, an even 300 at a relatively low lift(450-500). Now compare prices on blocks. A Big Gas block compared to a Ritter or an R. No, they ain't the prettiest engine, but, beautiful engines don't fuckin win races.