# Why do so many cars have exactly 276 hp? **URL:** \ **Category:** Factual Questions\ **Created:** [November 13, 2010, 8:41pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589 "2010-11-13T20:41:14Z")\ **Posts on this page:** 19\ **Page:** 1
**Author:** ![snailboy](https://avatars.discourse-cdn.com/v4/letter/s/97f17d/32.png) [@snailboy](https://boards.straightdope.com/u/snailboy)\ **Post date:** [November 13, 2010, 8:41pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/1 "2010-11-13T20:41:14Z")
This has probably been discussed but it’s hard to search for. It may only be Asian cars as I don’t remember seeing an American or European car advertised with 276 hp. I figured maybe there was a law in Asian countries that limited how much power a car could have and that 276 hp equated to some more even number of kilowatts, like how sportbikes are limited to 186 mph which equated to 300 km/h. However, 276 hp is 205 kW which is still a pretty odd number. So why are so many cars at this power level and why such an odd number instead of 200 kW or 250 hp? ---
**Author:** ![thirdname](https://avatars.discourse-cdn.com/v4/letter/t/d07c76/32.png) [@thirdname](https://boards.straightdope.com/u/thirdname)\ **Post date:** [November 13, 2010, 9:01pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/2 "2010-11-13T21:01:23Z")
Googling “276 horsepower” turns up this: [http://www.caranddriver.com/news/car/05q1/japan\_dumps\_276-hp\_pact-car\_news](http://www.caranddriver.com/news/car/05q1/japan_dumps_276-hp_pact-car_news) > [@](#): > > Since 1989, Japanese automakers have all endorsed—at least on paper—a kind of gentlemen’s agreement that limited their advertised horsepower to 276 on domestically produced vehicles. Their primary goal was to avoid a horsepower war in a country where the maximum speed limit is 62 mph. But in October, Honda officially broke the agreement at its Legend (Acura RL in the U.S.) press conference when it unveiled the model’s 300-hp, 3.5-liter V-6. ---
**Author:** ![snailboy](https://avatars.discourse-cdn.com/v4/letter/s/97f17d/32.png) [@snailboy](https://boards.straightdope.com/u/snailboy)\ **Post date:** [November 13, 2010, 10:27pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/3 "2010-11-13T22:27:31Z")
So it’s simply an unofficial agreement as with the sportbike speed limiter. I’ll note that the commercial that inspired me to ask this was for Kia, so it’s not strictly Japan. I’m still left wondering why they would choose the number 276 though. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [November 13, 2010, 10:34pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/4 "2010-11-13T22:34:05Z")
When did the term ‘horsepower’, as it is used today, come into common use? ---
**Author:** ![BorgHunter](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BorgHunter](https://boards.straightdope.com/u/BorgHunter)\ **Post date:** [November 13, 2010, 10:53pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/5 "2010-11-13T22:53:02Z")
> [@Johnny\_L.A](#): > > When did the term ‘horsepower’, as it is used today, come into common use? Wikipedia says [1702](https://secure.wikimedia.org/wikipedia/en/wiki/Horsepower#History_of_the_unit). There’s a later date of 1783 where James Watt and Matthew Boulton standardized 1 hp = 33,000 ft-lb/min, which is what it is equal to today; presumably the term had already been in wide use as a back of the envelope unit before then. ---
**Author:** ![FoieGrasIsEvil](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/foiegrasisevil/32/16638_2.png) [@FoieGrasIsEvil](https://boards.straightdope.com/u/FoieGrasIsEvil)\ **Post date:** [November 13, 2010, 10:54pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/6 "2010-11-13T22:54:45Z")
> [@snailboy](#): > > So it’s simply an unofficial agreement as with the sportbike speed limiter. I’ll note that the commercial that inspired me to ask this was for Kia, so it’s not strictly Japan. I’m still left wondering why they would choose the number 276 though. Kia has a 276hp vehicle? Wow. ---
**Author:** ![snailboy](https://avatars.discourse-cdn.com/v4/letter/s/97f17d/32.png) [@snailboy](https://boards.straightdope.com/u/snailboy)\ **Post date:** [November 13, 2010, 11:16pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/7 "2010-11-13T23:16:19Z")
> [@FoieGrasIsEvil](#): > > Kia has a 276hp vehicle? > > Wow. That’s what the commercial said, though I don’t remember which model it was. According to **thirdname** ’s link however, it may actually have more despite being advertised at 276 hp. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [November 14, 2010, 1:02am UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/8 "2010-11-14T01:02:07Z")
> [@BorgHunter](#): > > Wikipedia says [1702](https://secure.wikimedia.org/wikipedia/en/wiki/Horsepower#History_of_the_unit). There’s a later date of 1783 where James Watt and Matthew Boulton standardized 1 hp = 33,000 ft-lb/min, which is what it is equal to today; presumably the term had already been in wide use as a back of the envelope unit before then. At the bottom of that Wiki page you’ll find that I’m cited as an External Link, which takes you right back here: [What’s the difference between horsepower and torque? - The Straight Dope](http://www.straightdope.com/columns/read/2215/whats-the-difference-between-horsepower-and-torque) FWIW I don’t know what happened to the images; they seem to have been lost in a server move. I’ll see if I can fix them. ---
**Author:** ![BorgHunter](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@BorgHunter](https://boards.straightdope.com/u/BorgHunter)\ **Post date:** [November 14, 2010, 1:57am UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/9 "2010-11-14T01:57:27Z")
> [@Una\_Persson](#): > > At the bottom of that Wiki page you’ll find that I’m cited as an External Link, which takes you right back here: [What’s the difference between horsepower and torque? - The Straight Dope](http://www.straightdope.com/columns/read/2215/whats-the-difference-between-horsepower-and-torque) Woof. I should have remembered that column, considering I read it when it came out. ---
**Author:** ![Bill\_Door](https://avatars.discourse-cdn.com/v4/letter/b/50afbb/32.png) [@Bill\_Door](https://boards.straightdope.com/u/Bill_Door)\ **Post date:** [November 14, 2010, 12:29pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/10 "2010-11-14T12:29:48Z")
> [@snailboy](#): > > So it’s simply an unofficial agreement as with the sportbike speed limiter. I’ll note that the commercial that inspired me to ask this was for Kia, so it’s not strictly Japan. I’m still left wondering why they would choose the number 276 though. I wonder why myself. My first instinct was to say “Aha! 200 kilowatts converted to horsepower.” That was wrong as wrong can be. 200 kilowatts is only 268.2 HP. I got nothin else. ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [November 14, 2010, 12:40pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/11 "2010-11-14T12:40:51Z")
> [@snailboy](#): > > I’m still left wondering why they would choose the number 276 though. Presumably that was the power of key model(s) when the agreement was made. I’ve a “2.5 liter” engine pick-up which is actually 2.49 liters. A full 2.5 liters would put it in a higher tax class. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [November 14, 2010, 2:03pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/12 "2010-11-14T14:03:50Z")
Anyone that played Gran Turismo 1 and 2 on playstation one will remember that all the Japanese cars were listed at 276 HP despite apparent differences in performance. Polyphony Digital did the same as the car manufacturers, the cars were listed at 276HP in the game but had very different characteristics when driven in the game. ---
**Author:** ![opmike](https://avatars.discourse-cdn.com/v4/letter/o/9d8465/32.png) [@opmike](https://boards.straightdope.com/u/opmike)\ **Post date:** [November 14, 2010, 3:36pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/13 "2010-11-14T15:36:52Z")
> **[Why Japan finally got its foot off the brake](https://www.japantimes.co.jp/life/2008/04/13/travel/why-japan-finally-got-its-foot-off-the-brake/)** > > No other phrase more eloquently captures the essence of Japan's car industry than jishu-kisei, or 'mutual self-restraint.' > [@](#): > > The maximum engine power produced by the fastest domestic cars at the time was around 280 hp, so a ceiling of 280 hp was implemented by all carmakers — because all of them wanted to show they were trying to reduce fatalities. It was thought at the time that high speeds and road deaths were more directly linked than they are. > [@](#): > > But merely making such a sweeping statement on power outputs was not enough to capture the imagination of motorists. So the 280-hp power ceiling’s introduction in 1989 was timed to coincide with the launch of a high-profile sports car packing exactly that much horsepower — the Nissan Fairlady Z (300ZX). In the ensuing years, scores of high-performance Japanese cars, employing better engines with each new generation, arrived in showrooms — but all bearing the same 280-hp tag. ---
**Author:** ![Peremensoe](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@Peremensoe](https://boards.straightdope.com/u/Peremensoe)\ **Post date:** [November 14, 2010, 3:54pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/14 "2010-11-14T15:54:35Z")
Note, horsepower figures cited in association with motor vehicles are the power output of the _engine_, not the whole vehicle. One actual horse produces much more than one horsepower, because he’s got to move himself; “one horsepower” is what’s then _left over_ to do useful work. A “300hp” pickup truck hauls or tows a whole lot less than three hundred horses. ---
**Author:** ![SanDiegoTim](https://avatars.discourse-cdn.com/v4/letter/s/85e7bf/32.png) [@SanDiegoTim](https://boards.straightdope.com/u/SanDiegoTim)\ **Post date:** [November 14, 2010, 6:33pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/15 "2010-11-14T18:33:53Z")
May not be totally relevant to this conversation, but it’s worthy of note… Because HP is nothing more than a mathematical calculation using torque and RPM level, a manufacturer can “adjust” HP rating by rating either of these two factors differently. For example, stating that max. torque is available at 3,000 RPM vs. 3,500 RPM will change the HP rating. Don’t know if any do it, but it’s very doable. ---
**Author:** ![Dallas\_Jones](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dallas_jones/32/3277_2.png) [@Dallas\_Jones](https://boards.straightdope.com/u/Dallas_Jones)\ **Post date:** [November 14, 2010, 6:55pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/16 "2010-11-14T18:55:53Z")
Advertised horsepower claims are often marketing decisions. The fifth generation Corvette, or C5, was rated at 350 hp with the 5.7 liter LS1 engine. The same engine was put into the Camero SS and Firebird Trans Ams for 2001-2002 the last years those cars were made. These Cameros and Trans Ams even had the next generation LS6 intake manifolds, just like the Corvette, but were rated at 325 hp while the Corvette was rated at 350 hp. GM marketing did not want the cars to compete with each other based on hp alone, because the Corvette cost twice as much. ---
**Author:** ![muldoonthief](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/muldoonthief/32/3188_2.png) [@muldoonthief](https://boards.straightdope.com/u/muldoonthief)\ **Post date:** [November 15, 2010, 2:44pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/17 "2010-11-15T14:44:47Z")
Apparently there’s a thing called 1 metric horsepower, which is 735.5 watts as opposed to the imperial horsepower of 746W. Converting 276 imperial horsepower to metric gives 280 metric horsepower. At least 280 is a rounder number than 276. ---
**Author:** ![control-z](https://avatars.discourse-cdn.com/v4/letter/c/eada6e/32.png) [@control-z](https://boards.straightdope.com/u/control-z)\ **Post date:** [November 15, 2010, 3:41pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/18 "2010-11-15T15:41:51Z")
> [@FoieGrasIsEvil](#): > > Kia has a 276hp vehicle? > > Wow. I had to look that up. It’s an SUV, the Kia Sorento SX: [http://www.roadandtrack.com/tests/impressions/2011-kia-sorento-sx](http://www.roadandtrack.com/tests/impressions/2011-kia-sorento-sx) ---
**Author:** ![snailboy](https://avatars.discourse-cdn.com/v4/letter/s/97f17d/32.png) [@snailboy](https://boards.straightdope.com/u/snailboy)\ **Post date:** [November 15, 2010, 4:04pm UTC](https://boards.straightdope.com/t/why-do-so-many-cars-have-exactly-276-hp/560589/19 "2010-11-15T16:04:24Z")
> [@opmike](#): > > [Why Japan finally got its foot off the brake - The Japan Times](http://search.japantimes.co.jp/cgi-bin/fv20080413pl.html) > [@muldoonthief](#): > > Apparently there’s a thing called 1 metric horsepower, which is 735.5 watts as opposed to the imperial horsepower of 746W. Converting 276 imperial horsepower to metric gives 280 metric horsepower. At least 280 is a rounder number than 276. Now that makes a bit more sense of the number.