I had a 240 engine builder/mechanic here at a local shop who specializes (not very well) in Z32's and 240s tell me that it is impossible to make over 450whp on stock cams. Also, stock intake manifolds are impossible to make high hp with because they are "too long" and I guess that with stock exhaust mani's its impossible to make over 500hp as well. lol. I guess the long intake manifold prevent Greg @ SZ or Octavian from making 850+whp.