A Brief History of Automotive Horsepower

Bugatti makes some of the fastest and most powerful hyper sportscars on the planet. The horsepower of these magnificent supercar thoroughbreds stretches the boundaries of the imagination. Take the remarkable Bugatti Chiron, for example. It has reigned as one of Bugatti’s most powerful and fastest supercars, thanks to its incredible 1,500 bhp (base horsepower) W16 engine.

That was until the mind-boggling Bugatti Bolide Concept debuted earlier this year. Designed as the ultimate expression of Bugatti’s “Pur Sang” (pure blood) racing lineage, the Bolide’s prodigious 8.0-liter, quad-turbocharged W16 engine produces an utterly astonishing 1,824 base horsepower. With a top speed of 310 mph, the Bolide is simply one of the fastest supercars in the world. And one of the most powerful.

By comparison, the 1903 Bugatti Type 5’s “Hermes” engine produced 45 horsepower (which was stupendous for its time).

Whether it’s 45 horses or more than 1,800 horses, to fully understand how horsepower became the universal standard of measuring mechanical power output, we must travel back in time to when horses were just beginning to be challenged by a new form of motive power: steam.

Watt an Idea!

It was all about marketing.

In 1763, a Scottish engineer named James Watt (the same person from whom we get the term “watt” as a unit of measurement) had just developed a more efficient steam engine.

Watt needed a clever gimmick to convince people they should replace their familiar horses with his new steam-powered gizmo.  So, he hit upon the idea of comparing the power output of his steam engine with that of horses. After all, he reasoned, everyone can relate to a steed’s impressive strength.

It was a no-brainer.

So, he set about calculating the power output of horses and came up with an approximate figure of 33,000 pound-feet per minute for one horsepower. He did this by tying four draft horses to a mill shaft and observing them as they circled the shaft approximately 144 times an hour. He estimated that one horse could push with a force equivalent to 180 pounds. (Or the equivalent of one horse raising a 33-pound bucket of water from a 1,000-footwell in one minute.)

Performance with a Twist

Because Watt’s goal was to sell steam engines, he wasn’t too fussy about the accuracy of his calculations. Nevertheless, he and his partner, Matthew Boulton, pushed for this measure of horsepower to become the standard and it is still in use to this day.

Watts in a Name?

While most of us are familiar with the term “horsepower” (conventionally abbreviated “hp”), there are many different variations of horsepower that are used to describe power output. These include metric horsepower [“hp(M)”], electrical horsepower [ hp (E)], and boiler/steam horsepower [hp (S)]. Interestingly, various countries use their own unique designations for horsepower. Germany, for example, uses the term “Pferdestärke,” which is abbreviated “PS.”

How the SAE Measures Horsepower and Torque

By standardizing the measurement of automotive engine power, the government (for tax purposes) and consumers can make an “apples-to-apples” comparison of horsepower across different automotive brands, makes, and models.

Originally, the Royal Automotive Club (RAC) developed an early formula to calculate what was referred to as “taxable horsepower.” Subsequently, the Society of Automotive Engineers (SAE) established their own industry horsepower standards.

Before 1972, this was called “brake horsepower” (bhp or gross horsepower) and was measured using a stock engine devoid of any accessories, such as radiators, alternators, and even water pumps. After 1972, this standard was replaced by the SAE’s current “net horsepower” rating which is measured at the engine’s crankshaft. Engines are tested with all standard production accessories, giving a more “real-world” assessment of the engine’s true horsepower output. In 2005, the SAE introduced a new, voluntary standard called “SAE Certified Power” which conforms to more rigorous International Standards Organization (ISO) 9000/9002 certification.

Performance with a Twist

When it comes to brilliantly engineered powerplants like Bugatti’s ultra-powerful W16 engines, torque is literally where the “rubber meets the road.”

Essentially, torque is a measurement of the rotating force produced by an engine’s crankshaft. This differs from horsepower in that it measures the capacity for an engine to translate the power coming from the crankshaft into the motive “twist” needed to propel the vehicle forward.

Since different engines create torque at different powerbands, torque is usually measured in units of pound-feet (lb.-ft.) relative to an engine’s rpm. This is because the amount of torque delivered through the crankshaft and transmission to the wheels fluctuates depending on the rotational speed of the crankshaft. On the Bolide, for example, maximum idle-to-redline torque ranges from a low of 2,000 rpm to a high of 7,025 rpm.

An engine will deliver maximum horsepower at a certain rpm while generating the most torque at a certain “sweet spot” in-between the engine’s low and high rpm range. Ideally, the perfect engine produces enough torque at a low rpm and can sustain it through its redline. Moreover, the bigger the engine the more air it gulps, producing more horsepower and torque.

The beauty of Bugatti’s magnificent engines is that they produce an almost linear power output between these low and high rpm thresholds. And that translates to an unprecedented level of hyper-performance that must be experienced to be appreciated.

The Ultimate in Thoroughbred Performance

If you’re in the market for ultra-fast cars for sale near Miami, let us introduce you to our curated collection of some of the world’s most powerful, prestigious, and desirable Bugatti cars for sale in South Florida.

For unbridled power and a transcendent driving experience like no other, our Braman Bugatti Miami dealership offers an incomparable stable of the world’s most magnificent supercar thoroughbreds. Whether it’s the Bugatti Chiron, the Bugatti Veyron, or the Bugatti Divo, your definitive Bugatti ownership experience awaits at Braman Bugatti Miami.

We invite you to contact us today by calling 786-577-5216. Or stop by our Bugatti dealership near Coral Gables FL, conveniently located at 2060 Biscayne Blvd, Miami FL 33137.