What's the difference between BHP, HP and PS? - Mike's Mechanics

When talking about engine power figures, the car world uses so many different units that it can quickly become a bit of a mess. There's horsepower, brake horsepower, PS, kilowatts... what one should we all use?! Let DriveTribe's engineering nerd Mike Fernie take you through what each of these power units are and how they all compare.

What would you like Mike to explain next? Drop down into the comments with what you’d like to know!

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[sofakingtouge]

Only true measurement of power is the SP or Shrute power. Developed by Dwight Shrute. It comes from measuring the time/distance it takes his cousin Moes to carry a bushel of beets across the field. It is simply the superior unit of measurement.

[jeremymartens]

In Germany we use kW since 2000s. But we decided it into 2 parts. Scientific and public. My first car for example, a 1996 audi a4 had 74 kW / 100ps on paper. We always mention both, so you can relate

[spacecowboy]

"The now trendy metric system". I never thought I would see the adjective "trendy" coupled with "metric system" in te same sentence. Maybe "simple", "intelligent", "smart", "practical", "reasonable", but "trendy"... well, never! I guess that's what you get from people who'd rather carry a unit conversion table around instead of just multiplying by powers of 10!

[ghostofsparta]

This guy deserves a trophy for his simplicity in the way of an explanation
accuracy with the information
And the funy exciting and intresting video to watch ..
Respect to where respect is due
One of the best videos out there in YouTube
and Am a subscriber!

[downup]

Sorry bud, you’re a little confused on hp vs bhp. US market cars only measured horsepower without accessories and often with different intakes and exhaust manifolds before 1972. That was known as Gross HP. The newer standard from 1972 onward is Net HP, which requires the engine to be configured as closely as possible to how it will be installed in the car, so with full air filter, alternator, catalytic converters, everything, exactly the same as in the UK

[joeshittheragman]

How do you ask a brit about the power of his car ? U WATT M8 ???

[benitobento]

a kilogram of steel or a kilogram of feathers

[Babishabascule]

CV is only used for fiscal purposes in France. We use CH the rest of the time.

[grendelum]

3:36 _”...the now trendy metric system...”_

*Science:* 🙄

[nickcook]

Joules, Watts, Newtons, Coulombs and Amperes are the only units of measurement we require.

[corystansbury]

Uhhh... What was described for HP vs. BHP is the difference between gross and net HP. The US hasn't used gross HP since 1971. US HP numbers include all accessories and representative/prototypic intake/exhaust systems.

[frisco-.]

In Germany/Europe every car's power ist rated by kilowatts!
Even in the papers there is the kilowatt configuration.

[mattdobz]

I wouldn't use watts to measure the power of an internal combustion engine, and I wouldn't use horsepower to measure the power of my kitchen appliances. It would not be British of me to not use metric and imperial units at the same time and switch between them randomly, particularly when one's fuel capacity is measured in litres whereas fuel consumption is measured in miles per gallon.

[Vaijykone]

I would prefer kilowatts, because it seems to be the simplest and quite possibly the most accurate of these options.

[psychoalert]

KW is the official measurement of power in thermodynamics
1 KW = 1, 34 HP = 1, 36 PS

[migteleco]

Hola!
Here in Spain we use CV, which here stands for "Caballo de Vapor", and is translated as "steam horse" (literally "horse of steam") similarly to our french neighbors.

[Smittel]

To avoid further confusion, a global standard will now be adopted, the floopityshoophoop, which is 1 harkfordsning per swippedy

[dufonrafal]

What you’re saying about HP, or SAE HP more specifically, was true before 1971, but not anymore.

[dxme]

1. It's written and spoken Pferdestärken and not Pferdstäke
2. Instead of PS, KW is officially used here in Germany, but probably around 90% are still using PS, if not than even more (Most of the video games are mainly the only who are using KW in Germany)

[andreaskorth]

One horsepower is not lifting 33.000 lbs one foot. That's 15 tons and no horse could lift this kind of weight even an inch. HP has been defined as lifting 330 lbs 100 feet, which is also more realistically achieved in a minute.