Best Bang for the Buck: Horsepower

Price: $13,499 | HP: 150 | $/HP: $89.99

Talk about starting off in left field. It's hard to imagine a more incongruous car when talking horsepower and performance. But the Suzuki SX4 Sport's bargain-basement price and decently powered little 4-cylinder engine give it an excellent price-to-horsepower ratio when paired with the standard manual transmission. You do get what you pay for, however. The Suzuki's quality and refinement lag compared with cars from Honda and Toyota, for example. On the upside, the SX4 Sport is a nimble little car. It's still a far cry from a Honda Civic Si or Volkswagen GTI, but then so is its price.

Read:  10 Great Cars for Less Than $20,000

Price: $24,645 | HP: 274 | $/HP: $89.95

Most Hyundai Sonatas come with a 4-cylinder engine, which is good for gas mileage but only adequate in delivering performance. But the 2.0T gets a turbocharger, which transforms this sedan into something more exciting, even though at its core the car will always be just another family hauler, despite what's under the hood. Still, with 274 horsepower, the engine pulls strongly, and the handling dynamics aren't bad. Since it's a Hyundai, the Sonata is packed with features and comes with a great warranty, making it one of the best values around, regardless of the horsepower.

See: New Sedans With More Than 250 Horsepower

Price: $48,810 | HP: 550 | $/HP: $88.75

This one's no surprise. It's a muscle car, and muscle cars are all about offering the most performance for the lowest cost. Now, $48,810 isn't exactly cheap, but the Shelby GT500 is no ordinary muscle car. Its 550-horsepower V8 engine offers performance on par with sports cars costing at least twice as much. Unlike American muscle cars of the past, it can do more than just go fast in a straight line; the Mustang chassis on which it's built is wonderfully balanced. And with its stiffer suspension, the Shelby GT500 handles corners even better.

View Pictures:  Shelby GT500 Super Snake

Price: $26,750 | HP: 306 | $/HP: $87.42

The Hyundai Genesis Coupe is a Korean muscle car: It's sporty, it has rear-wheel drive, and it's affordable. It comes in many flavors, too. The one with the best power-to-price ratio is the base version — called the R-Spec — equipped with a 3.8-liter 306-horsepower V6 engine and a 6-speed manual transmission. This combination gives a lot of performance per dollar. In concept, the Genesis Coupe is similar to American muscle cars, but in reality it provides a different driving experience than, say, a Chevrolet Camaro or Ford Mustang; it's smaller and the suspension setup is firmer.

Read:  10 Foreign Cars With Muscle-Car DNA

Price: $23,995 | HP: 283 | $/HP: $84.79

Chrysler has pulled off a miracle. It has systematically upgraded every vehicle across all of its brands — including Dodge — on thin budgets while preparing future products to replace the current lineup. The Avenger is competent and much better than before, thanks mainly to two things: a better interior with classier styling and materials, and the company's new Pentastar 3.6-liter V6 engine. It puts out 283 horsepower while still managing to offer an estimated 29 mpg on the highway. Is it as refined as V6 engines from Asian competitors? The jury's still out on that one.

Bing: Dodge Accessories

Price: $23,165 | HP: 283 | $/HP: $81.86

The Chrysler 200 replaced the Sebring and we're glad for that; it is a marked improvement in many ways. As twin to the Dodge Avenger, the 200 has the same new Pentastar V6, but in SXT Touring trim it's more affordable than the most affordable version of the Avenger that comes with the V6. That's why it ranks higher on this list. Although they're mechanically the same, the Chrysler and Dodge sedans have different characters. The 200 is more sophisticated, while the Avenger goes for a sporty, younger feel.

Compare: Chrysler 200 vs. Buick Regal vs. Mitsubishi Galant

Price: $29,995 | HP: 370 | $/HP: $81.07

Dodge drastically improved the Charger R/T for 2011, and the good news for 2012 is that the company is holding the line on pricing. That means you can get a 5.7-liter Hemi V8 engine for just less than $30,000. No other automaker sells a car like the Charger in the United States at the moment: a large, powerful, rear-wheel-drive sedan at an affordable price. Although 370 horsepower sounds like a lot, the Charger is big and heavy, so it ends up being just enough power for good acceleration. Still, this is a lot of car for the money.

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Price: $29,995 | HP: 376 | $/HP: $79.77

The Dodge Challenger is the Charger's 2-door sibling. It has six more horsepower under the hood. Most people won't be able to tell the difference. The reason to get a Challenger over a Charger is styling versus practicality: It's sleeker but not as handy, with two fewer doors than the Charger. Compared with the Chevy Camaro and Ford Mustang, this big coupe feels fat and flabby. But it has a comfortable ride and the Hemi makes it entertaining enough. Upgrading to the pricier SRT8 version on either the Challenger or the Charger brings more power, but it isn't as good a power value.

View Slideshow:  Manly Machines

Price: $31,850 | HP: 426 | $/HP: $74.77

If we were ranking cars based on attitude per dollar, the Chevrolet Camaro would win hands-down. Its aggressive appearance is intimidating. Drivers hustled out of its way when they saw us approaching in the rearview mirror. And both young and old exclaimed how impressive it was when they came across it on the street. The SS version gets a power boost with a 426-horsepower V8. That's supercar power at a fraction of the cost of a Ferrari or Porsche. The Camaro is a well-rounded performer, even though it doesn't feel quite as lively and tossable as a Ford Mustang.

Watch Video:  Face-off: Mustang vs. Camaro

Price: $29,310 | HP: 412 | $/HP: $71.14

The Ford Mustang GT offers 14 horsepower less than the Chevy Camaro SS, but it's less expensive. So it edges out its arch rival in this price-to-power competition. Numbers aside, Ford has fine-tuned this car to near perfection. Its Achilles heel is the interior, which, although much improved over that of past Mustangs, still feels cheap. Dynamically, the Mustang is a joy to drive on both road and track. It's beautifully balanced, and the V8 engine in the GT version gives awesome acceleration. A slew of improvements are coming for 2013, including more power for the V8 in the GT model, and a 650-horsepower Shelby GT500.

View Slideshow:  10 Cars That Make Us Thankful

For more information on any vehicle in this slideshow, click the links below:

- Suzuki SX4
- Hyundai Sonata 2.0T
- Ford Shelby GT500
- Hyundai Genesis Coupe 3.8 R-Spec Manual
- Dodge Avenger SXT Plus
- Chrysler 200 Touring
- Dodge Charger R/T RWD
- Dodge Challenger R/T
- Chevrolet Camaro Coupe SS
- Ford Mustang GT Coupe

Compare: All 10 cars

Matthew de Paula wanted to be an automotive journalist ever since reading his first car magazine in grade school. After a brief stint writing about finance, he helped launch ForbesAutos.com and became the site's editor in 2006. Matthew now freelances for various outlets.

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