I would be taking a look at some of the Tamiya models for possible rubber offerings. Sometimes you gotta really dig to find tire specs. Better yet, get some 2.2 wheels. I had some (Lazer's wheels?) on my Optima with no problems. The choices for off-road buggy tires is diminishing. 2.2" Pro-Line Calibers, or Blockades, but are soft compound. Check out some of the Schumacher offerings in 2.2" buggy tires if you do decide to go with 2.2" tires.