Shelby GT500KR 2008

Scope of this guide

This guide is scoped to the Shelby GT500KR (2008 to 2009), the King of the Road edition of the Ford Mustang Shelby GT500 that was finished by Shelby in Las Vegas. It is a two-door coupé with a front-engine layout, rear-wheel drive and a supercharged, intercooled 5.4 litre V8 under the hood, paired with a Tremec six-speed manual gearbox. The name was chosen to mark the 40th anniversary of the original 1968 Shelby GT500KR. This page covers only the 2008 and 2009 model years of this car. It is not a guide to the standard GT500 it was built from, and it is not a guide to any later Shelby with a similar name.

We have not driven this model for this article. We are an editorial desk that reads sources, and everything below comes from pages we opened: the Wikipedia article on the fifth-generation Mustang, a Ford press release dated 20 March 2008 (reproduced on a university-hosted mirror of Ford media pages), a PCarMarket auction listing, an RM Sotheby's lot page, a Mustang specification page, Oneshift, FordMuscle and a ConceptCarz valuation page. We have not inspected, owned or tested a car. Cars like this rarely come to market in large numbers, so this page is for research, not a buying recommendation, and it cannot replace an inspection by a specialist who knows the Shelby GT500 family.

The figures at a glance

• Engine: 5.4L supercharged V8, front-engine, with a quoted displacement of 5,408 cc (330 cubic inches), four valves per cylinder and a compression ratio of 8.4:1 according to the Mustang specification page.
• Drivetrain: rear-wheel drive through a Tremec TR6060 six-speed manual gearbox, with a 3.73:1 rear axle ratio instead of the 3.31:1 used on the standard GT500.
• Power: 540 bhp at 6,250 rpm. The sources print this as 540 hp, with Wikipedia adding 547 PS, and RM Sotheby's prints 540 bhp. We use 540 bhp throughout.
• Torque: 691 Nm at 4,500 rpm. Wikipedia prints 510 lb ft, which is 691 Nm, and the same Wikipedia entry prints 691 N.m directly. Multiplying 510 by the standard conversion of 1.35582 gives 691.5, so we show 691 Nm.
• 0-100 km/h: no figure shown. The sources give 0-60 mph times of 4.3 seconds (estimated) and 4.0 seconds, and a 0-60 mph time is not a 0-100 km/h time, so we have not converted or relabelled either of them.
• Top speed: no figure shown. None of the pages we opened states a top speed for the GT500KR.
• Years: 2008 and 2009 model years.
• Production: 1,712 cars in total, made up of 1,000 cars for 2008 plus 712 for 2009, according to the PCarMarket listing. Other sources count the 2008 cars a little differently, as explained below.

History and what changed

Ford's own press release says the 2008 GT500KR was the fourth limited-edition Mustang from the Shelby and Ford collaboration since 2001, and that it builds on the GT500 with its 500 hp supercharged engine. Production of the 2008 car began on 11 January, which was Carroll Shelby's 85th birthday, with dealer arrivals expected in spring. Each car starts life as a GT500 built at the AutoAlliance plant in Flat Rock, Michigan. It then goes to Shelby's Las Vegas facility, where the performance pack, the exhaust, the shifter and the unique body, chassis and interior parts are added. The release says each car is hand-customised and delivered in an enclosed transporter. Oneshift describes the car as engineered by Ford SVT and final-assembled by Shelby Automobiles, which is a slightly different way of describing the same split.

What Shelby added

The changes listed by the pages we read include:

• Power: a Ford Racing power upgrade pack with a revised calibration, a cold-air intake and a performance exhaust, lifting output from 500 hp on the GT500 to 540 bhp. FordMuscle says the gain came from the upgraded exhaust and a calibration that needs premium fuel, with more aggressive timing.
• Gearing and shifter: the 3.73:1 rear axle ratio and a short-throw shifter.
• Suspension: unique springs, dampers and stabilizer bars. Oneshift says wheel rates are 17 per cent higher at the front and 7 per cent higher at the rear, and the ride height is lowered by 20 mm at the front and 15 mm at the rear. Wikipedia adds a Ford Racing strut tower brace.
• Brakes: the Mustang specification page lists 14-inch vented Brembo front discs with four-piston calipers and 11.8-inch vented rear discs.
• Aero and body: a carbon fibre hood with functional scoops and twist-lock pins, a carbon fibre front splitter and mirror caps, functional brake cooling ducts, and a revised rear spoiler. Oneshift says the splitter and spoiler add front-axle downforce.
• Wheels and tyres: 18 by 9.5 inch machined aluminium wheels with Goodyear Eagle F1 tyres, sized 255/45 at the front and 285/40 at the rear.
• Trim: seats with Carroll Shelby's signature embroidered on the seats and headrests, 40th Anniversary badging, and a Shelby CSM dash plate.

Wikipedia says the car weighs about 22 lb, or 10 kg, less than a standard GT500. Oneshift says the car stops six feet shorter from 60 mph than the GT500 and reportedly sustained 1.0g of lateral acceleration on the skidpad in slalom runs. Those are magazine claims we could not check.

2008 against 2009

The March 2008 press release announced a second year. It says an additional 746 cars would be built for the 2009 model year to meet worldwide demand, of which 571 were for United States customers, matching the 1,571 cars of the original 1968 run. The remaining cars were intended for countries that did not receive 2008 cars. The release says performance and features were the same as the 2008 edition, with 540 hp, the 3.73:1 axle, the short-throw shifter and the unique suspension tuning. The one stated difference is that the 40th Anniversary badging appears only on the 2008 special edition and not on the 2009 cars.

Which figures we chose, and why

Power and torque

The 540 figure is consistent across every page that gives one. Wikipedia, the Ford press release, the Mustang specification page, RM Sotheby's, Oneshift, PCarMarket and FordMuscle all print 540. Wikipedia and the Mustang specification page both place the peak at 6,250 rpm and call it 40 hp above the GT500. We use 540 bhp. Torque is given as 510 lb ft at 4,500 rpm by Wikipedia, the specification page, Oneshift and PCarMarket, and the Ford press release does not state torque at all. The Mustang specification page marks both the power and torque as estimated, so they are factory-style figures and not dyno results.

Acceleration and top speed

The pages disagree on 0-60 mph. The Mustang specification page and FordMuscle give 4.3 seconds, with the specification page marking it as an estimate. RM Sotheby's lot description gives 4.0 seconds, which it attributes to the 40 hp gain and the 3.73 axle ratio. Wikipedia gives no time for the GT500KR; the only 0-60 mph figure in its article is for a later GT500. We could not decide between 4.3 and 4.0 and neither is a 0-100 km/h figure, so there is no figure shown for 0-100 km/h. The same pages give a quarter mile of about 12.1 seconds (FordMuscle) and 12.5 seconds at 114 mph (specification page, estimated). No page we opened gives a top speed, so there is no figure shown for that either. We saw a top speed mentioned in a search summary of a page we could not open, and we have not used it.

Production count

This is the figure where the sources disagree most, so we spell it out.

• Wikipedia: 1,011 cars for the 2008 model year, including prototypes, plus another 712 for 2009. Adding those gives 1,723.
• PCarMarket: one of 1,000 40th Anniversary Editions built for the United States in 2008, out of 1,712 GT500KRs in total. This matches 1,000 plus 712.
• RM Sotheby's: the lot is described as one of 1,000 built, and the page does not give a 2009 figure.
• Ford press release: 746 cars planned for 2009, with 571 for the United States, which is the planned number and not the built number.
• FordMuscle: roughly 1,700 across the two years.
• Mustang specification page: it lists 1,011 coupes for 2008 and also cites 1,000 planned, 1,712 overall and a two-year figure of 1,571 that includes 571 cars for 2009. It contradicts itself.

Our reading is that 1,000 was the planned 2008 run, that 1,011 counts 11 additional prototypes, and that 712 is the 2009 total. That makes 1,712 the figure for production cars and 1,723 the figure including prototypes. We use 1,712 because a source states it directly for exactly this model. The 571 figure for 2009 looks like a planning target chosen to match the 1968 run, and we do not treat it as a count of cars built.

The Mustang specification page also gives a colour split for the 2008 cars: 476 in Silver Metallic with Vista Blue stripes, 328 in Ebony Black, 107 in red with silver stripes and 100 in Vista Blue. These add up to 1,011. A reader comment on that page says the red is correctly called Torch Red, not Colorado Red.

What to check before buying

Only a couple of the pages give specifics, so this is a short list and not a full inspection scheme. It also reflects what these cars arrive with, not a promise that any particular car has it.

• Identification: the RM Sotheby's page gives a CSM number (08KR0269) and a chassis number for its car, and the PCarMarket listing gives CSM number 08KR0989. The Mustang specification page lists an official Shelby CSM dash plate. Matching the CSM number to the car and its paperwork is the obvious first check.
• Paperwork: the PCarMarket car came with the original window sticker, owner's manuals and sales literature. RM Sotheby's says the Shelby window sticker showed over $35,000 in upgrades over a standard GT500. Original documents are what support a claim about a numbered car.
• Clutch history: the PCarMarket listing records an updated clutch fitted by a Ford dealer in 2010 under service bulletin TSB-09-9-2. We found no other recall or fault information for this car, so ask any seller whether that work was done.
• Originality: the listing notes door panels redone in 2022 and a CD player that was not working properly. It is a reminder to ask what has been replaced, particularly the carbon fibre pieces, the hood pins and the interior trim.
• Year: the 40th Anniversary badging is stated to be on 2008 cars only, so check that the car's badging matches the model year it is advertised as.

A specialist inspection is still the sensible step, and so is checking live listings before relying on any price quoted here.

Market and value notes

We found no reliable new-price figure. The Mustang specification page lists a starting price of 120,000 dollars, which we could not reconcile with anything else we read, so we have not relied on it. RM Sotheby's window sticker detail of over 35,000 dollars in upgrades is the only price evidence for the work done by Shelby.

On the used side, ConceptCarz bases its valuation page on 74 auction sales. Its median sale is 57.2 thousand dollars, with condition bands running from 39.2 to 51.7 thousand for fair, 51.7 to 57.2 thousand for good, 57.2 to 69.3 thousand for excellent and 69.3 thousand upwards for perfect. Its median by year is 55 thousand dollars for 2025, with sales between 44 and 62.7 thousand dollars, and its most recent sale is 70.4 thousand dollars at Mecum Kissimmee in January 2026. The highest sale it lists is 550 thousand dollars, and the Ford press release mentions a one-of-a-kind glass-roof car that sold for that amount at Barrett-Jackson, so we suspect the two are the same car, although neither page says so. Individual results we read include a PCarMarket sale of 48 thousand dollars in August 2023 for a car with 4,792 miles, and an RM Sotheby's result of 77 thousand dollars for a car with fewer than 1,000 miles, where the page gives no sale date. Valuation pages summarise past auctions and are not a guarantee of what any car will fetch.

What we could not find

• No top speed and no 0-100 km/h time: no figure shown for either. The 0-60 mph times we found are 4.3 and 4.0 seconds and they disagree.
• No official torque figure from Ford: the Ford press release does not state torque, so the 510 lb ft figure comes from Wikipedia and the other pages that repeat it.
• No agreed production total. We chose 1,712 and explained why.
• No recall list, reliability data or repair costs beyond the single clutch service bulletin noted on one listing.
• Several pages would not open for us: a parts retailer page (access refused), a specification database (access refused), a forum repost of an Edmunds follow-up test (access refused) and Hagerty past-sales pages (sign-in required). We did not work around any of them, and we have not used what we saw of them in search summaries.

About the photograph

The page uses the catalogue photograph for this model, and its credit is listed on the credits page.

Verdict

The Shelby GT500KR is best understood as a Shelby-finished, numbered GT500 with 40 more horsepower, a shorter axle ratio, firmer suspension and carbon fibre outside, made for the 40th anniversary of the first King of the Road. Our figures are 540 bhp and 691 Nm from a 5.4L supercharged V8, with no figure shown for 0-100 km/h or top speed because the sources only give 0-60 mph times and no top speed. The production total is the shakiest number, and 1,712 is our best-supported reading. If you are researching one, check the CSM number, the paperwork and the clutch history, and treat this page as a research aid rather than a buying recommendation.