When people think of a fast car, they tend to think of something that looks fast and stands out from the crowd, like a supercar. Car enthusiasts with a fast car love to make it look even faster with big wheels, big body kits, big exhausts, etc. Weirdly though, many car enthusiasts love fast cars that look like any normal car.

A car that looks like every other car but goes faster than a sports car or a supercar, sleepers are loved not only by enthusiasts but also the police who use them as undercover cop cars as they're fast and completely discrete.

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10 Ford Taurus SHO

1999-Ford-Taurus-SHO
via carbuzz

The Ford Taurus SHO is a proper sleeper. In fact, for most, it is the definition of a sleeper car. It looks like a normal Taurus, but under the hood, it is so much more than a big family sedan. The cops loved this car as it was just so unassuming. The Taurus SHO was made between four generations of the Taurus.

motorauthority.com

The last Taurus SHO was made between 2010 and 2019, and it featured a 3.5 liter EcoBoost twin-turbo V6. It has 365hp and 350 lb-ft of torque which is more than an EcoBoost Mustang. It hits 60 in 6.6 seconds which is pretty decent too. It is a very discrete car and there are many facts about it, including that the Taurus SHO was featured in the Hollywood Blockbuster Men in Black. 

9 Mercury Marauder

Black Mercury Marauder from side
via Motoring Research

The Mercury Marauder is a real sleeper car. It's based on the Crown Victoria, a car which is normally used as a New York taxi or a police car. The Marauder is an evil-looking car, and it is completely stealthy. Most people won't know how powerful this car really is. Under the hood is a Mustang 4.6-liter V8 with 302hp which pushes the car to 0-60 in 6.8 seconds.

Black and Shiny Mercury Marauder front third quarter hd wallpaper view
Via: Bring A Trailer

It is a car that looks so understated. Because the Crown Victoria is so popular, this car can move anywhere without any stares from anyone. However, if this car is in your rearview mirror then you will certainly feel the chills a little as it looks like an FBI car.

8 Audi S6 C6

Audi S6 quarter front
Via Cars And Bids

The Audi S6 C6 is a proper sleeper car that really blows your mind. It looks like a normal A6 albeit with the bigger wheels and four exhausts as well as the V10 badge. Under the hood though, things are completely different. It's powered by a Lamborghini-derived V10, which is nuts. How many sedans do you know apart from the RS6, the S8, and E60 M5 that have a V10 under the hood?

autoevolution.com

It is the most unassuming car ever. The S6 outside looks like a salesman's car. Inside it's very boring. There's nothing boring under the hood though. The power is 429hp and 398 lb-ft of torque with a 0-60 time of around 4.8 seconds.

7 Mercedes 500E/E500

autoleitner.nl

This car is such a sleeper that even the name doesn't sound sporty. The 500E is a car that is very special. It was a joint project between Mercedes and Porsche and the reason why it was a joint project, was that the 500 E/E500 would not fit through the assembly line at the Mercedes factory due to how wide the fenders were. The 500E/E500 was tuned by Porsche with a more powerful engine, better suspension brakes, etc.

magazinauto.com

Under the hood was a 5.0 V8 from a Mercedes SL. It had 322hp and 354 lb-ft of torque and did a 0-60 time of around 5.5 seconds. The press called it "the wolf in sheep's clothing," as it looked like a normal E-Class, yet it could easily catch the likes of the E34 M5 and Sierra Sapphire at the time. It couldn't catch the Lotus Carlton though, as that was just too quick.

6 Volvo S70/V70 R

via MotorBiscuit

The Volvo V70/S70 R is a completely understated car. The 850R was the one that got all the praise and interest, whilst the V70/S70 R was rolled under the carpet. It's a five-cylinder monster with the first-gen model having 247hp (later first-generation models had 261hp). It did a 0-60 of just over 7 seconds.

It's a car that UK police used quite regularly as it was just so understated. The second-generation car had 296hp and a 0-60 of around 6.5 seconds. It's not M3 fast but the beauty of it is that it looks like a normal car, even in its weird teal color.

5 Mercedes E55 AMG

Mercedes-Benz E55 AMG
Via mecum.com

Here's a car that actually kick-started the AMG hype. Modern AMG cars are very aggressive-looking indeed, but the original ones such as the E55 are far from aggressive. The E55 in all honesty looks like a normal E-Class. It may have four exhausts and a lot of badges, but ultimately it is an understated car.

Mercedes-Benz E55 AMG W211
via mecum.com

Under the hood is a 5.4 liter supercharged V8 with 469hp and 516 lb-ft of torque. It had so much torque, that Mercedes had to fit it with a 5-speed auto instead of a new 7-speed gearbox. It was stupidly quick, doing a 0-60 time of 4.1 seconds, which was faster than the Ferrari 360 and Lamborghini Gallardo at the time. In wagon form, this thing looks even more understated.

4 GMC Syclone

1991 GMC Syclone
tfltruck.com

The GMC Syclone is a cool-looking truck and the only exterior differences between the Syclone and a normal GMC Sonoma (the truck the Syclone was based on), was wheels, body kit, and decals. To most people, it just looks like a cool truck. It doesn't at all look like a sports car killer.

Via Mecum

Under the hood is a 4.3-liter turbo V6 with 280hp and 350 lb-ft of torque. It had similar horsepower figures to a Honda NSX supercar at the time. A new Syclone was reported to hit 60 in 4.3 seconds which is faster than a stock BMW F82 M4. It's a car you don't expect to be that fast since it's a proper truck that can carry many things.

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3 Chrysler 300C SRT8

Chrysler 300C SRT8 at a parking
Via conceptcarz.com

The Chrysler 300C is a properly fat car. It looks bulky, and it certainly has a lot of presence. The SRT8 though is surprisingly subtle despite it being the top model. It has larger alloys, a nicer grille, a slight body kit, and a spoiler. Nothing much at all to really set it apart from other cars, but it is a quick car.

2005-chrysler-300c-srt8
via topspeed

The original 300C had 425hp and 420 lb-ft of torque. The second-generation car had 470hp and 470 lb-ft of torque. A decent amount of power from a car that doesn't look too fast at all.

2 BMW M550i

Courtesy Motor1.com

Even veteran petrolheads would have a hard time spotting an M550i. It just looks so much like a normal 5-series, yet it hits 60 in under 4 seconds. The M550i has always been a sleeper, and the current model shares the same engine as the M850i and now has over 520hp and over 550 lb-ft of torque.

via caranddriver.com

It is a super sedan and in some ways, it is a budget M5. It certainly isn't slow at all. In fact, it does a faster 0-60 time than an original C12 Zonda hypercar.

1 Audi S8

The front of a D3 Audi S8
favcars.com

The Audi S8 is a serious sleeper that was made to outrun supercars. It has always been a special car, and it too once had a Lamborghini V10. The second V10 sedan Audi has made after the S6 and before the RS6. It is the ultimate getaway car having been used in films such as Taken and The Transporter.

topspeed.com

The S8 is a full-on understated car. It looks pretty much like a big Audi sedan rather than anything fast. The latest car is promising a 0-60 time of almost 3 seconds. That's supercar speed in a car that looks more like a businessman's car.

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