2004 911 Carrera 4S Cabriolet X51 6-Speed

The Porsche 996 Carrera equipped with the X51 Power Kit offered a factory upgrade that boosted the 3.6-liter naturally aspirated flat-six engine’s output from 316 to 345 horsepower. Introduced as an optional package, the X51 included enhancements such as revised cylinder heads, a more aggressive camshaft profile, a larger intake manifold with a unique plenum design, a sport exhaust system, and additional cooling improvements were also part of the package to manage the increased performance. While subtle on the outside, X51-equipped Carreras delivered sharper throttle response and a broader powerband, making them a rare and coveted variant among enthusiasts.

This 2004 Porsche 911 Carrera 4S Cabriolet is a rare example equipped with the factory X51 Carrera Power Kit. Showing just 19,457 miles on the odometer, it came finished in Slate Grey Metallic over a Natural Grey Supple Leather interior with a Black soft top. Outfitted with a six-speed manual transmission, the car also featured xenon headlights, heated comfort seats, aluminum interior accents, and a Bose sound system. The car was part of RM’s Shift Online sale and looked to be in nice condition, although not much in the way of service history was offered with the car. Either way, a rare example with nice, low miles.

Over the last twelve months, 996 C4S Cabs have averaged $35,400 with a high of $65,000 for a non-X51 example with 13,000 miles on the odometer. The closest X51-equipped car I have in my data was a 14,752-mile example that hammered for $55,000 back in June of last year. Our Spotlight car sold for $48,400* all-in, which looks like a solid deal for a car with just 5k more miles that the other X51 above.

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