A commonly available 16" size is 255-50-16 from various tire brands.... BFG G-Force T/As are what I run on for my street/hwy/HSAX/HPDE events... decent performance... but 340 tread wear rating... your mileage may vary.... I have vintage mini-light rims 16x8 ("Performance" brand, from Australia).
For my serious pylon AX or road course HSAX competition events, I've run Hoosier A6 275-45-16 tires (DOT) on my lt-wt Centerline 16x10 rims front/rear... will eventually get a new set A7 or R7. Hoosiers stick like glue... only issue is classifications allowed, as well as limited lifetime wear (roughly 60 minutes, 120-180 minutes at best max time on tracks).
BUT, perhaps somewhere in my future will be set of 18x10-11s to run the popular 200 tread wear rated tires... at least 275- or else go for 315- front and rear (squared).... $$$$ overall!!!