Both cars are big fun, but we've observed the Protegé's performance to fluctuate from one vehicle to another, hinting at production variations. Unlike the Mazdaspeed Protegé, which has a turbo kit supplied by Callaway, Mazda's hot-rod Miata wears a factory-developed and -installed turbocharger kit, as well as a heavier-duty clutch and revised suspension. The turbo itself is virtually transparent-you can't even hear it with the top up-and it suffers so little lag that the car mostly feels naturally aspirated. On a purely subjective level, the Mazdaspeed car feels wholly transformed, capable of top-gear traffic slaloms at just a jab of the pedal. A top-gear 50-to-70-mph time of 7.6 seconds is pretty respectable and four seconds better than the 142-hp model's. But since midrange engine response is stronger in the turbo Miata, too, there is less call for downshifting on the open road. Gear shifting is critical in a car that gobbles ratios during hard acceleration like a bear in a Burger King Dumpster, and the Miata can be shifted as fast as is humanly possible. The action is thus as light and direct as it has ever been and preserves one of the car's most important entertainment assets. Beefing up this gearbox for its bigger job involved shot-peening of internal gearwheels along with a fourth-gear ratio change so slight you have to go to three decimal places to appreciate it. Mazdaspeed's Miata is based on the normal model's LS trim level and is equipped with the optional six-speed transmission. HIGHS: Good power, nimble handling, charming character, fantastic bargain. We had to promise to be gentle with the prototype vehicle you see in these pictures, but even so, the car was 1.4 seconds quicker to 60 mph and over a second faster through the quarter than the last Miata we tested. We recorded a 6.7-second sprint to 60 mph and expect slightly faster results from production cars.

2004 mazda protege 5 horsepower