With only 350 cars built, the Jaguar XJ220 is a collector's item, but some examples are rarer than others.

Having relied heavily on Tom Walkinshaw Racing for the development of the XJ220 in the first place, Jaguar turned to the outfit when it came time to assess the possibility of a competition version. Three XJ220C race cars were born as a result, but in order to homologate them for competition, Jaguar and TWR built six roadgoing examples dubbed XJ220S. One of them is now going up for auction.

To create the XJ220S, TWR removed all the aluminum bodywork (except the doors) and replaced it with carbon fiber, adding a front splitter, rear wing and wider side sills in the process. That helped drive weight down to just over 1,000 kg (2,200 lbs), while the twin-turbo V6 was retuned to deliver 680 horsepower.

This particular car's owner recently had TWR install a titanium exhaust and recalibrate the engine output to nice round 700 hp. He also had it repainted the same shade of grey as the Lamborghini Reventon, fitted more modern headlights, and refurbished the magnesium wheels. As a result, RM Auctions expects it to fetch between $225,000 and $300,000 when it crosses the block in Arizona next month. Full details in the auction listing after the jump.

Lot 127 - 1993 Jaguar XJ220S Coupe

Estimate:
$225,000-$300,000 US
Est. 700 bhp, 3.5-liter twin-turbocharged V-6 engine, five-speed manual transmission, four-wheel independent suspension, and four-wheel disc brakes. Wheelbase: 104"

• One of only six built
• Recent major mechanical overhaul and restoration
• Twin-turbocharged, 700-horsepower engine
• Jaguar style and performance at its pinnacle

The original Jaguar XJ220 was introduced in the late 1980s as a concept; response was so strong that Jaguar enlisted Tom Walkinshaw Racing to conduct a feasibility study to determine if a production series would be possible. Although production was promised to be limited to just 350 units, Jaguar took deposits for 1,500 cars, which was then pared back to the originally promised limit.

The standard XJ220 had a body built of aluminum. TWR modified nine of these cars; three examples were transformed into the XJ220C to compete in GT racing, while the other six were designated as XJ220S. The XJ220S model, like this example, was comprised of five "standard" units and one additional "modified" version. They were produced as road-going cars built to comply with homologation requirements.

The Walkinshaw-built Jaguars were stripped of their aluminum body, save for the door skins. The original panels were replaced with carbon fiber and the XJ220Ss were also given a front splitter, wider sills and an adjustable rear spoiler. The additional body kit produced an even more menacing stance than that of the production XJ220. The carbon-fiber panels helped reduce the curb weight to a lithe 2,379 pounds, impressive for an 18-foot long Jaguar. The twin-turbo V-6 powerplant was overhauled to produce a whopping 680 horsepower and over 526 foot-pounds of torque.

The current owner of chassis number 784 has retained it for the last eight years. Over that period a great deal of time, effort and money have been expended to add substantial performance and value to this already impressive supercar. The owner opted to have a proper titanium exhaust system by Tom Walkinshaw Racing installed at a cost of nearly $20,000. An expert from Spain was flown in to install the exhaust as well as perform a major service on the engine. This included replacement of all belts, injector cleaning as well as recalibrating and updating of the computer software. The result of this work is an outstanding output of approximately 700 horsepower. The brakes and clutch have also been serviced.

The XJ220S was painstakingly repainted to match the Lamborghini color of Reventon Gray, making this supercar even more intimidating in a very contemporary color. Furthermore the leather interior was completely refurbished, and Infiniti projector headlights were also added. The original magnesium wheels were also refurbished and fitted with brand new tires. Since the early 2000s the owner has added about 1,200 miles to the odometer and only precious few since the cosmetic and mechanical overhaul completed this past year. It has been shown and won accolades at SEMA and is followed by a loyal group of devotees. Most other examples of the rare XJ220S reside in museums or in vast car collections and as a result have attained a mythical status. These special Jaguars deliver style and performance that is truly on par with more contemporary supercars yet arguably remains the most undervalued member of the species.