[Bruce Lancaster]

I gather that most of the really serious racers make their own chambers. One of our local draggers used to run different brand heads left and right to annoy the peanut gallery...both had been welded flat and new chambers hand-carved to his supersecret recipe, so anything up there was irrelevant anyway.
Flatdog told me a bit about the superduper high-level telephone circuit with people like Kloth. No one would divulge anything substantial, especially the total shape of their chambers, but they would drop hints about flow experiments on something like effect of lowering the ceiling over the valves...if someone else was seeing similar trends, a few more hints would be exchanged. Very, very guarded. I am sure that if I had walked into Flatdog's garage unannounced when a chamber was exposed he would have had to kill me, even though I am nowhere near these high levels of scientific inquiry!