You know how Mazda said 2001 miata's had 155 hp, well, they LIED! All car mags said they found little performance increase, some were even slower than the previous years (they gained 80 pounds). So Mazda checked, and they had re-worked the cats for federal emission regs. They make 142 hp. If you don't like it, Mazda will buy back your miata for the full purchase price. If you keep it, you get 500 bucks, adn free maintanence for the duration of your warranty.
Apparantly Mazda forgot to re-check the engines power after they 'fixed' the cats.
At least they made it easy to tune miata's, just get high-flow cats, and voilla! 13 (at least) extra horsepower.
What do you think about that!