Speed, at its root, is a simple equation; maximum power with minimum weight. The venerable V8 engine was an expression of the first element, the nearly perfect ratio of power and torque in a size that could fit in a modern-sized car with an easily managed 'harmonic' balance. That's the weight of the cylinders moving back and forth inside the engine. They were easily tuned, and power adders can manage to create unreal amounts of power.

On the flip side, the compact and microcar is an exercise in efficiency. By making the car smaller, it requires less power to move it, meaning the engine can be smaller and more efficient. For countries rebuilding after wars or looking to mobilize its workforce, they were meant to give people who don't have a lot of money for big flashy cars to have the same freedom. They were an attempt to do more with less.

It was only a matter of time for hot rodders to put these two great tastes together to make something unreal. Powerful engines in tiny cars can equal neck-breaking acceleration and speed, but a small car with an engine that's almost half the size of the car can also make striking and weird-looking cars. Here are 21 pictures of small cars with ridiculously big engines.

21 Big Bad VW Caddy

The Volkswagen Caddy, or Rabbit Pickup, was part of a segment that's more or less lost in the U.S. these days: the coupe utility. At the time, it had contemporaries in the Ford Courier and the Subaru Brat (the latter fixed with jump seats in the bed to make it a different class of vehicle for tax and insurance purposes). They were meant as light-duty trucks that drove like their coupe counterparts.

Pickups have long been a hot rod platform because of their lack of body weight, especially in the rear, combined with their strong chassis.

This Caddy has been given the hot rod treatment with a big V8 that can't fit under a hood. With that much power in that small a package, it's likely hard to keep in a straight line as well.

20 On-Fire Fiero

In the mid-'80s, Pontiac did something unexpected. With the style cues borrowed from the contemporary Trans Am, they made a two-seater mid-engine car. Putting the engine between the axles provides a balance of weight that makes pivoting through the corners a more even prospect. Mid-engine cars handle so well that most purpose-built race cars are built that way.

The most powerful Fiero of the time came with a V6, which wasn't enough for this hot rodder.

While the mid-engine layout is meant for cornering, putting the engine on the rear axle can also be good for acceleration, which is why you see the engine in the back on dragsters. This person has turned a corner carver into a quarter-mile burner with its rearview-obscuring supercharged V8.

19 Massive Metropolitan

The Nash Metropolitan was a car so ahead of its time in the U.S. that it had to be built by Austin in England because the cost for tooling a small car in the '50s was too expensive. At the time, U.S. manufacturers were all about bigger and bigger cars. Nash wanted to make a 'second' car, one for the wife to drive around on errands. It was the first car marketed specifically for women, with Miss America being its first spokesperson. With a design by Pininfarina (with the understanding that they wouldn't tell anyone), the car quickly found a cult following. Of course, being small and lightweight, it was only a matter of time before someone put a big blown V8 in it, as well as apparently increasingly smaller Metros stacked on top of that.

18 Vengeful Vespa

Vespa is better known for its distinctive scooters loved by Mods and Hipsters alike, but at one point, there was also a microcar carrying the Vespa name made by ACMA, French makers of the Italian scooter. Like its other micro car contemporaries, it was an exercise in minimalism with a small 400cc engine in the back. That, of course, wouldn't do. Instead, this rod builder has put in it a blown V8 so big, it's hard to imagine how the pilot of this lightweight power wagon sees where he's going. Built for the quarter mile, though, all that matters is that it goes in a straight line as fast as possible. All they need to see is the Christmas tree.

17 Gizmoe

The Gremlin was AMC's second attempt to make a compact car to compete with import cars that were entering the U.S. market and deal with rising gas prices. The chopped-off cabin that was a shortened version of their full-size car was a "love it or hate it" proposition for most buyers, but it was a bit of a success for the fading brand. While the AMX version did come with a V8, it didn't include this hood-busting blower attachment. Named after the adorable Mogwai from the movie Gremlins, it looks like someone fed it after midnight.

16 Mega Beetle

The Volkswagen Beetle is one of those import cars that the Gremlin was designed to compete with. The Beetle was a lot of things, but with its initial 1,200cc air-cooled engine or even its 1,600cc engine hanging off the back, fast was not one of them. Hot rodders have been known to milk some horsepower out of the factory pancake engine, but the hot rod motto of 'there's no replacement for displacement' is taken to heart with this hot rod, replacing the rear four-cylinder with a classic U.S.-made V8 up front.

15 V8 Golf Cart

Golf is a long, boring game filled with a lot of strolling from hole to hole. To make up some of that time, the golf car was invented. With small engines or electric motors, they only need to be faster than walking and not so out of control that they mess up those nice pretty greens. Some might feel like there's no fun in that, especially when you're using your golf cart as a pit vehicle to ferry you from the paddock to the pits. So, this active individual has fitted his golf cart with a beastly V8 so they can reach their ball before it lands.

14 Fast Fiat

When Wally Sparks and the rest of the hot rod crowd were forming the NHRA, they were fitting modern V8s out of Cadillacs and Buicks in pre-war cars stripped down to their bare bones. While old Model As and Ts made great platforms, a few inventive speed hunters found even lighter platforms in British Austins and Italian Fiats, small cars from countries that didn't have the big expansive roadways we enjoy in the United States. The Fiat Topolino is a popular platform for garage builders looking for that quick quarter mile. To fit a big V8 in the diminutive Italian car, they have to extend the front axle, and the V8 is still half the length of the car.

13 Fiat 500 Funny Car

The more drag racers modified their cars for the quarter mile, the less they looked like proper cars. Chopping and channeling the cars down to their bare speed basics with bodies that were little more than shells placed on frames resulted in what became known as 'funny cars.'

This Fiat 500 has been given the 'funny car' treatment with a custom tube frame with the body laid on top.

It's hinged because there isn't enough structural support for a functioning door; you lift the entire body to get in. To fit the V8, it's been shifted from the rear to the front, displacing way more than the stock 500cc engine from which the car gets its name.

12 CR-X Beast Mode

The Honda CR-X was meant to be an even smaller, more efficient version of the growing Civic. In that capacity, it succeeded. The car, in its high-efficiency trim, managed an astounding 50 mpg in the 1980s without the benefit of a hybrid motor. The short wheelbase and light weight also made it a favorite of tuners, and the car gained a reputation as a cheap and fun performance car for the people willing to tweak it. There's still an upper limit to what the tiny four-cylinder can do, however, so this one's been fitted with as big a V8 engine as the chassis will allow. No doubt, its straight-line speed should be something to behold.

11 Massive Midget

The Miata may be the two-seater sports car of record for today, but it is, in fact, an homage to the cars of the mid-twentieth century that defined the category. One of the most successful of the breed was the affordable and fun MG Midget. Initially offered with engines under a liter in size, the car was a lightweight sports car for the masses like the Miata today. Carol Shelby became a legend finding a way to take a British two-seater to epic speeds by fitting Ford V8s in AC and Sunbeam cars. This MG has gotten the same treatment in an even smaller package, allowing the builder to take on a Cobra. Turning a car this small with this much weight up front might be a little tricky, though, especially if it's putting down that much power out the rear wheels.

10 The Nerdy Jock

Every high school has at least one studious athlete, the one that holds up the track team and the academic decathlon. The Mercedes-made SMART ForTwo was meant as a city car, able to fit in tight parking spaces and navigate crowded cities. In the U.S., it has its devout followers, though some have criticized its not-impressive-enough mileage for its size and being too small to survive the U.S.A.'s SUV-filled roads. There are those, however, who see a chance for the old formula of tiny car and big V8. Like the Topolino before it, it's a quarter-miler cinch, pushing a car whose biggest weight is the engine down the track. Even with an extended front axle, though, that much power in a short wheelbase isn't for the faint of heart.

9 Double-Engine Messerschmitt

The Messerschmitt name might be familiar to fans of World War II documentaries as the main manufacturer of Germany's diving fighter-bombers. After the war, the company needed to find more peaceful things to make, and like the Isetta, they set out making a small affordable car to get citizens on the move. The result was the KR200, a three-wheeled car with a unique tandem seating arrangement that resembled their old airplanes. The car had a small cameo in the movie Brazil, thanks to its alien looks. Here, the tiny 200cc engine, along with most of the bodywork, has been done away with in order to fit not one, but two massive blown V8s during the crazy early "anything goes" days of drag racing.

8 Frightful Fairlady

The small nimble Nissan goes by a lot of names. It's part of the Z GT line called the "240z" in the US, the "Fairlady Z" in Japan, and the "S30" internally. In the United States, it was also a Datsun until Nissan folded up the brand in the '80s. The car was meant to compete with European GT cars, specifically the aging MG B-GT. It was a modern design with an inline six with an "impressive for its time" 151hp. This power, with its affordability, made it one of the most successful sports cars of all time. Of course, the inline six had its limits, limits that can be conquered with a V8 engine so big, the hood and the front bodywork had to be removed. For good measure, they added a cantaloupe-sized turbocharger.

7 Mega Monster Miata

The Mazda MX-5 Miata has been carrying the banner for the affordable two-seater sports car for almost 30 years now. Because of its rampant success, there are a lot of even cheaper Miatas laying around waiting to be modified and customized. T

here's even a niche aftermarket supplier that sells kits and customs that allow Miata owners to fit Mustang-sourced V8s in the lightweight roadster to turn them into modern Cobras.

There are some that aren't content with a simple 300hp V8 in a car that weighs less than a ton, so this one has cut the hood to accommodate a massive supercharger. The canyon-carving characteristics are likely lost but more than made up for in neck-snapping acceleration.

6 Mad Tracker

In the early '90s, GM decided to make a brand to compete with Japanese economy cars by teaming up with three of them. For their last model, the Tracker, the company they teamed up with was Suzuki, and they made their version of the compact SUV. It was a sister car to the Suzuki Sidekick that replaced the troubled Samurai. Powered by a tiny 80hp engine, it wasn't a stunner. So Vinnie Barbone took that engine out and replaced it with a 900hp twin-turbocharged 454 V8. He needed to extend the chassis 4 inches just to get it in. This also meant getting rid of the 4-wheel drive and replacing the front and rear with bits from a Mustang II.

5 Maximum Mini

BMW's revival Mini Cooper has been a huge success with its iconic looks and fun driving characteristics.

While the supercharged and later turbocharged four-cylinder has been plenty for most Mini owners, this one wanted a little more, so he turned to Hoonigan, the people behind Ken Block's insane gymkhana Mustang, to add a twin-turbocharged 350 V8 putting out 546hp.

While it looks like it has wider front-wheel track common in front-wheel-drive drag cars, that's actually just to fit the engine in. The rear end comes from a Toyota Forerunner.

4 Wheel-Standing Chevette

The Chevette has few fans. The half-hearted attempt at an economy car by Chevrolet was unsightly and suffered from poor build quality. Today, there are only a few left on the road. This also makes them a cheap and easy platform for people looking for a vessel to put their big bad V8 in. This one has a seriously big bad V8, to the tune of a 555-cubic-inch twin-turbo V8 pumping out an estimated 1,500hp. That's some body-twisting power in one unloved small car from the '80s that has run the car down the quarter mile in the mid-seven-seconds at a speed no Chevette was ever meant to achieve.

3 Austin All America

Like the 240z, the Austin America went by a lot of names. Whatever it was called, it was meant as a small passenger car that was a good 'around town' car that had the engaging driving dynamics of the popular Mini. They came in two-, three-, and four-door versions. Like the Mini, however, it came with small engines, a 1,100cc and a 1,300cc version. While other V8 swaps have been ungainly beasts, this one is neatly tucked away with bulging bodywork, only given away by the large drag tires in the back.

2 Muscular Frog

Before the MG Midget, there was the Austin Healey Sprite. The Sprite was so successful that the other Healeys were referred to as 'big Healeys.' Eventually, the Sprite would become a sister car for the Midget, but the first generation was its own car with a distinct body style that gave it the nickname "Bugeye" or "Frogeye" sprite.

From the factory, it had an engine less than a liter in size with double-digit hp figures.

That was more than enough for a car weighing close to a thousand pounds. More than enough isn't a limit for hot rodders, though, so this one has a massive V8 stuffed under the iconic Bugeyed hood.