Interesting. Go ahead and voice your opinions. If we can all do that without being petty we will learn more. I'm an engineer as well. By nature, I tinker with stuff. Can't help myself. I've been racing on and off for decades as well. My brother had some of the Kyosho Platinum shocks that had 2 stage pistons that were externally adjustable for float with an outer shock shaft that you could turn. I've always thought that two stage pistons made a great deal of sense. The RC Shox worked better in my car than the #1's with 25 weight. And that was without doing anything further with hole diameters.

Is there something to consider with hole shape? Given the right amount of control, you could add different edge breaks (angles or depth) to the hole on top and bottom. In theory, this would change the effective piston hole diameter depending on whether your shock was compressing or rebounding. Anyone with a decent drill press should be able to do this without a problem.

I'm not necessarily suggesting that any of this needs to be tried out or that it would make anyone's car turn quicker laps. But I am into RC as much for tuning and practicing as I am for the racing. Chiseling away at lap times on your home track is almost as satisfying to me (and way cheaper) than actually driving to a real track and racing. That's the great thing about this thread. Its a thread about understanding and learning.