Look at the Michelin Pilot Super Sports. They come in a huge variety of sizes, including 20 inch. From what I have been reading, they ought to be pretty decent auto-x tires. Not to mention a perfectly streetable upgrade from the p-zeros. Interestingly as well, these tires are significantly lighter than other brands in the same size. Like 4 to 5 pounds per tire.
And like I told you, I highly doubt that drag radials will pass tech inspection for auto-x.
K&N Typhoon, Spohn sway bars, Pedders front radius rod bushes, BMR cradle bushing inserts, Enkei Tuning Raijins (20.7 lbs ea.), Dunlop Direzza Z1 Star Specs, -2 front camber, -1 rear.