Factory-tuned Performance Cars: Part 3

To this point, we've worked our way through various versions of production cars that receive special tuning from the factory. From compact pocket rockets such as the Chevrolet Cobalt SS Supercharged to the burly Dodge Charger SRT8, this series has covered vehicles with prices up to $50,000.

While there are some mighty fine rides in that group, we would be remiss not to go any higher on the price spectrum. The cars with sticker prices above $50,000 are truly the cream of the high-performance crop. Though not designed to be sales leaders, high-end factory-tuned cars give manufacturers a "halo" vehicle, the kind most people only dream of owning.

From Europe
Audi is launching high performance versions of its compact A4, midsize A6, and large A8 sedans. While the company already has S4 sedans and Avant wagons with a 340-horsepower 4.2-liter V8 engine, Audi is taking the sedan a step further by releasing the RS 4 quattro. It's still a 4.2-liter V8, but this version packs 420 horsepower. Major props go to Audi for creating an engine with more than 100 horsepower per liter that doesn't rely on a turbocharger or supercharger.

Top: '07 Audi RS 4. Bottom left: '07 Audi S6. Bottom right: '07 Audi S8.

A 6-speed manual transmission and Audi's quattro all-wheel drive get all that power to the pavement. RS 4 is capable, according to Audi, of 4.6 seconds 0-60 mph acceleration. The RS 4 starts at $66,000.

Coming to North American shores later in 2006 are the S6 and S8 sedans. Based on the A6 and A8, respectively, the S6 and S8 go beyond their "normal" siblings by swapping out V6 and V8 engines for V10s. S6 will have 420 horsepower, and S8 will have 450. The engine borrows many components from the V10 found in the Gallardo coupe from Audi-owned Lamborghini. Pricing isn't available yet, but expect S6 to come in well over $75,000. S8 should check in at over $100,000, but less than the Gallardo's $175,000 asking price. That's big savings, which can be put to use towards a yacht or heck, another factory-tuned performance car.

Fellow German automaker BMW also has a roster of performance machines. Like Mercedes-Benz, BMW has a separate arm dedicated to taking the company's stock cars and transforming them, all while retaining a factory warranty. These cars leave their factories in Germany and the United States with the M designation. M is short for M-Technik (though it could just as easily stand for Muscular) and was initially created to support the company's racing efforts. The 3-Series, 5-Series, 6-Series, and Z4 models are all recipients of the M group's engineering wizardry.

The M3 premium compact coupe and convertible are being phased out right now. They're based on a design from 1999 and have a 333-horsepower inline 6-cyl engine mated to a 6-speed manual or 6-speed sequential manual transmission (SMT). BMW redesigned its 3-Series coupes and convertibles for 2007 and has not announced plans to offer an M3. The M3 coupes start at $48,900, the convertible at $56,600.

The premium midsize M5 sedan substitutes a 500-horsepower V10 engine in place of standard inline 6-cylinders or V8s. It teams with a 7-speed SMT and has a starting price of $81,200. BMW also put this engine into its large 6-Series premium coupe to create the M6. It also has a 7-speed SMT and is priced northward of the M5 at $96,100. The company recently announced plans to build an M6 convertible. Pricing isn't available, but expect it to start above $100,000.

Midyear 2006 saw the reintroduction of BMW's American-built Z4 M convertibles and hatchback coupes. These sporty two-seaters have freshened styling and more power versus their predecessors. While all Z4 models have inline 6-cyl engines, M versions have 330 horsepower, which is 75 more than the next most powerful version. A 6-speed manual is the only transmission. The M hatchback starts at $49,300, with the convertible slightly more at $51,995.

Continuing on this trip through Deutschland, Mercedes-Benz has many factory-tuned performance cars in its stable. Nearly all of its cars and SUVs are available with the AMG designation.

AMG is the Mercedes performance arm. This division was formed 38 years ago as an independent tuner of Mercedes vehicles. The 1995 C36, a 268-horsepower V6 version of the compact C-Class sedan, was the first car sold in the U.S. under official agreement between Mercedes-Benz and AMG.

In subsequent years, the AMG-tuned C-Class outgrew its V6 and 4-speed automatic transmission. The current model is called C55 and has a 362-horsepower 5.4-liter V8 and a 5-speed automatic. It also adds standard 18-inch tires vs. 17s on other C-Classes, as well as uprated suspension tuning and brakes. The C55 has a starting price of $54,450. Ironically, C55 is discontinued for 2007, making the C-Class the only model in Mercedes' lineup without an AMG-tuned version.

AMG's influence continues to spread through the rest of Mercedes' product portfolio. In the past, they simply picked cars off the assembly line and tweaked them. For 2007, AMG began building its own engines from scratch and dropping them into the appropriate vehicles. Add that to the other customizing AMG does; including specific tires and wheels, suspension tuning, brakes, and exterior and interior trim; and you have a fleet of vehicles that kick butt, as well as pamper it.

Mercedes' 2007 AMG lineup looks like this:

• CL-Class- Though Mercedes hasn't officially announced an AMG version of its top-line coupes for '07, '06 models should still be available. The CL55 has a 493-horsepower supercharged 5.4-liter V8 and a $125,000 base price. AMG shoves a 604-horsepower 6.0-liter turbocharged V12 under the hood of the CL65. Start saving your pocket change because the car will cost you $179,600.
• CLK-Class- The CLK63 is a 2-door convertible with a power fabric top and heated glass rear window. It has a 475-horsepower 6.2-liter V8 engine and 7-speed automatic transmission. Pricing isn't available, but expect it to be more than the $62,900 for the stock CLK550 convertible.
• CLS-Class- Essentially an E-Class sedan wrapped in different sheetmetal, the CLS63 will have a 507-horsepower 6.2-liter V8 engine. This replaces the '06 CLS55, which had a supercharged 469-horsepower 5.4-liter V8. Expect '07 versions to cost more than the $86,600 of the '06 CLS55.
• E-Class- Mercedes' restyled midsize sedans and wagons both get AMG treatment in the form of the E55. They share the 507-horsepower 6.2-liter V8 of the CLS-Class, as well as its 7-speed automatic. Though prices aren't available yet, they should cost more than the $81,800 for the 2006 E55 sedan and $82,600 for the E55 wagon.
• SLK-Class- The less costly of Mercedes' two-seat convertibles offers the SLK55 with AMG's tuning. Its 5.4-liter V8 produces 355 horsepower. Pricing for '07 is yet to be announced, but it shouldn't be much more than the '06 models' $61,500, a figure that's downright reasonable compared to the next two cars on this list.
• S-Class- AMG's engineers must have licked their chops when the revamed '07 S-Class sedan found its way into their labs. They took Mercedes' top-end sedan and outfitted it with a turbocharged 6.0-liter V12 engine that produces 604 horsepower, thus creating the S65. The V12's torque output is a curb-stomping 738 lb-ft. That's more than the combined torque ratings of the Chevrolet Aveo, Ford Focus, Honda Fit, Hyundai Accent, Nissan Versa, and Toyota Yaris. Mercedes says you can go from 0-60 mph in 4.2 seconds. What could go faster? How about the money from your bank account should you want to purchase one. This sedan will cost you $182,275.
• SL-Class- AMG versions of Mercedes' costliest two-seat convertibles carry over into '07, with the 510-horsepower supercharged 5.4-liter V8 SL55 and the 604-horsepower turbocharged 6.0-liter V12 SL65. Sticker prices are equally lofty, at $128,800 for the SL55 and a coronary-inducing $186,000 for the SL65.

Lastly, we roll out of Germany and into merry ol' England, where Jaguar produces its own line of premium factory-tuned performance cars. The British marquee gives its tuned cars the R designation. All of its models, except the compact X-Type can be had with this treatment.

Jaguar's midsize S-Type and large XJ Series sedans share their R-version engine, which is a supercharged 400-horsepower 4.2-liter V8. Combined with a 6-speed automatic transmission, the S-Type R is good for a 6.1 seconds 0-60 mph acceleration time, and you can expect the XJR to do about the same. In addition to engine modifications, Rs have specific suspensions, wheels, and tires to provide a sportier feel than their standard counterparts. Other visual enhancements include a wire-mesh grille. The S-Type R starts at $63,330, and the XJR will set you back $80,835.

Speaking of sporty, Jaguar just launched the R version of its redesigned '07 XK coupe and convertible. The XKR benefits from its siblings' all-aluminum construction and stiff frame. Like the S-Type and XJ, it too has a supercharged 4.2-liter V8, but XKR has 420 horsepower. Both coupe and convertible body styles will be available as Rs, and you can expect both versions to start well above their "base" counterparts' respective sticker prices of $74,835 and $80,835.

From Japan
While Japanese brands offer many different factory-tuned performance cars, they're all in the sub-$50,000 price range. That may change in the next 12 months, though, as rumors abound about Lexus offering the IS 500, a souped-up version of its premium compact sedan. The current top-end IS 350 has a 306-horsepower V6 engine, but the IS 500 would have a V8 with more than 400 horsepower. That would make the IS 500 the fastest production Toyota since the Supra Turbo of the 1990s. Stay tuned for further developments on this story.

From America
Like the Japanese, domestic automakers haven't dabbled much in the sciences of factory-tuned performance cars with sticker prices greater than $50,000. Chrysler doesn't have any models playing in this field (Viper doesn't count as it's a tuned model in and of itself), and there are no Fords, Lincolns, or Mercurys either. General Motors is the only automaker attempting to take on Europe's heaviest hitters with products built right in the U.S. of A.

Cadillac enters the fight with three different models, all of which carry the V designation. This lineup works just like BMW's M and Mercedes' AMG, and those German rivals are Cadillac's targets.

Top: '07 Cadillac CTS-V. Bottom: '07 Cadillac XLR-V.

First up is the CTS-V. Instead of tuning this model's 255-horsepower V6 engine with a turbocharger, supercharger, or revised internal components, Cadillac does the job with the brute force of good-old-fashioned American V8 muscle. The engine of choice is the Chevrolet Corvette's 400-horsepower 6.0-liter unit. Purists can take delight in the fact that the only available transmission is a 6-speed manual. CTS-V has unique styling cues, including a wire mesh grille, and 18-inch wheels on run-flat tires. With the BMW M3 and Mercedes C55 as its primary targets, CTS-V is priced accordingly at $50,770.

The larger STS-V positions itself as a rival to the BMW M5 and Mercedes E55. Though STS rides on a stretched version of the CTS architecture, GM tunes it much differently. STS-V has a V8 engine, but in this application it's a supercharged 469-horsepower 4.4-liter unit that teams with a 6-speed automatic transmission. It's the most powerful production Cadillac ever, and the company says it's capable of a 4.8-seconds 0-60 mph time. That may be a bit slower than the Bimmer or Benz, but STS-V is less expensive, with a base price of $74,445.

STS-V may be the most powerful production Cadillac, but the flagship XLR-V convertible is the most expensive. This two-seat convertible has a base price of $97,460. Add in a $1700 gas-guzzler tax and destination charge, and it's the first GM vehicle to have a six-figure sticker.

That price will get you a convertible that shares some of its platform with the Corvette, though obviously the two don't look anything alike, nor do they share engines. Like the STS-V, XLR-V has a supercharged 4.4-liter V8 engine and 6-speed automatic transmission.  The convertible has to make do with 443 horsepower, but Cadillac's claim of 0-60 mph acceleration at 4.6 seconds would make it faster than the STS.

And speaking of the Corvette, while the base models are fast in their own right (Chevy says 4.5-seconds 0-60 mph), they're still not the most powerful. Consider now the 2007 Corvette Z06. Instead of a 400-horsepower 6.0-liter V8 engine, Chevy drops in a 505-horsepower 7.0-liter V8. Sheer brute force propels this hot-rod 'Vette to an estimated 3.7-seconds 0-60 time. That's faster than many exotics with six-figure stickers. Not only does the Z06 cut down those cars on a straightaway, it also cuts them down on price. It starts at $69,175, which, among this entire crop of high-end factory performance cars, can be considered a bargain.

They're not cheap, but the lucky few who can pony up the Benjamins to get into these cars are virtually guaranteed smiles at every press of the pedal, flick of the gearshift, and turn of the steering whee