280hp power restriction and 180km/h speed limit in Japan. What is it about?

r3dster

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Some might wonder why 180km/h limit and 280hp max?
I got it off vwvortex.com.
a good read to share ;)
Happy Reading~

No other phrase more eloquently captures the essence of Japan's car industry than jishu-kisei, or "mutual self-restraint."


Either in terms of maximum engine-power output, maximum speedometer readings or speed limiters, Japan is the world leader in automotive moderation.

It all started back in the mid-1970s, when the police and government became concerned about the growing nationwide problem of bosozoku — street gangs on motor cycles and in cars who were speeding around disrupting traffic and ignoring road laws. The Japan Automobile Manufacturers' Association (JAMA) stepped in, suggesting that domestic carmakers put a ceiling on the maximum speed of all future Japanese- built vehicles by restricting the top speed markings on speedometers to 180 kph and imposing a speed-limiting device at the same speed. Once a vehicle reached 180 kph, this "speed governor" would automatically starve an engine of fuel and stop the car from going any faster.

Today, every vehicle produced in Japan for the local market comes fitted with a speed limiter set at 180 kph. Why carmakers made 180 kph their mark is not clear, but one industry insider suggested it was about the maximum speed that a standard domestically built car could go at the time. The policy was well-received by the general motoring public, who had urged authorities and carmakers to do something concrete to curb the gang problem and make roads safer. By the late '70s, a combination of police action and the speed limiters had led to a reduction in gang-related violence.

But the 180-kph limit also seemed like a good idea to the vast majority of drivers for the simple reason that the maximum speed allowed on expressways was only 100 kph anyway.

While the 180-kph speed limiter remains a uniquely Japanese phenomenon, and never ceases to generate considerable comedy among media and car enthusiasts from Europe and America — where many speed limiters engage at 250 kph — it is not the only measure of "mutual self-restraint" on the nation's roads.

A more prominent policy was introduced in the late '80s to solve another national crisis. In 1988, Japan's road fatalities reached an alarming figure of over 10,000 annually, causing JAMA to once again swing into action. This time it asked carmakers to restrict maximum engine power, or horsepower. Its reasoning was that this restriction, in conjunction with the 180-kph speed-limiter policy, would not only manage speeds but would head off an inevitable power war between domestic carmakers.

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.

Meanwhile, road fatalities had come down by the mid-'90s — thanks to rapidly improving safety features in vehicles such as multiple air bags, pretensioner seat belts, antilock brakes and impact-absorbing bodies — and industry experts began to question the link between speed and road fatalities.

They also began to argue that the 280-hp limit jeopardized Japan's world-class engine technology.

By this time, many of Japan's sports-car engines were capable of producing well over 400 hp, but they were all still restricted to 280 hp. As might have been expected, some cars, such as the Nissan Skyline GT-R, had already started to push the power envelope by generating — in reality — over 320 hp. But in typical Japanese fashion, these cars were still rated by their makers at 280 hp. The power ceiling was preserved for the sake of maintaining a decade-old gentleman's agreement — restricting domestic carmakers from competing on an even playing field with powerful overseas rivals who had already built cars packing 400- and 500-hp engines.

Growing dissent in the domestic industry culminated in a watershed year in 2004. Former JAMA Chairman Itaru Koeda went before the press in July 2004 to explain that his organization had in fact found no relationship between speed and road fatalities, which had fallen below 8,000 annually, and he had therefore called for an end to the 280-hp gentlemen's agreement. The gloves were now off, and Japan could punch its weight in terms of its engine muscle, unfettered on the international stage. Just as Nissan's Fairlady Z had been there to initiate the power ceiling back in 1989, another car was waiting in the wings to mark its abolition. That car, the Honda Legend, launched in mid-2004, and produces a modest 300 hp. Since then, of course, many other models have followed — among them the 308-hp Subaru Impreza STI, the 333-hp Nissan Skyline Coupe and the 380-hp Lexus LS460. But that's only the start. In addition to Nissan's just-launched 480-hp GT-R, Honda is working on a 550-hp two-door supercar, while Lexus is putting the final touches to its own 520-hp LF-A. Given that these last two supercars will cost more than ¥15,000,000 each to buy when they arrive by 2010, it makes you wonder whether the makers couldn't organize some self-restraint on the pricing side, too.

Peter Lyon is a a 20-year motoring journalist who covers Japan's auto industry for more than a dozen publications worldwide.
 

ken yeang

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This "regulation" applies to stock Japanese cars.
The regulation is roughly similar, to what we are seeing in F1, where there are "caps" in terms of money spent (esp big company with big budget vs small company with limited budget), on testing hours, allowed technology, etc.

This is very much like the Versailles Treaty (a Military restriction) signed by superpower countries to control and curb arm races among one another.

Dont get confused with modified cars with monster hp engine that we see the street in japan.
 

Waiora_ProTuner

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there some story that after WWII, US had 'prohibited' Japan from producing an engine that could powered an aircraft...at that time Zero Fighter was build by Mitsubishi..thus the gentleman agreement are made..

Additional 'story' is that, at that period of time the only dynamometer available to Japan is Bosch type. It could only measured up to 280hp..

Thus they 'advertised' it as 276~280hp...some engine proven to produce more than that, stock...

why the agreement still exist until few years ago?
its normal modern thing to avoid competition on engine power and size...

but, they still try to swiftly 'cheat' on the rules...like previously mentioned, RB26DETT produced more power advertised..same as 2JZ-GTE..
but the weird things is, these engine could produce about +100hp more without hiccup...why waste?

to look good with the government...with those 180km/h rules...
 

Ryuuken

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Something we dont see everyday! Kudos!
 

r3dster

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:listen: is a rare occasion to find "monsters" on japanese street.
Well, probably i was with the wife and daughter so looking for "street monsters" isn't a very good idea ;p would've been nice to be able to see how the scene would've been. sigh.
 

vr2turbo

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:listen: is a rare occasion to find "monsters" on japanese street.
Well, probably i was with the wife and daughter so looking for "street monsters" isn't a very good idea ;p would've been nice to be able to see how the scene would've been. sigh.
Just back from Japan last week. Was in Nagoya, and there are many many tiny cars nowadays. For fuel economy and parking space.
 

vr2turbo

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How's Nagoya? I think most of the monster cars are on Wangan at night? :driver:
4 years ago in Tokyo did see some power and nice cars, but Nagoya, no woh?:listen:

Small Cars like Nissan Note, Honda N Box and so on......:driver:
 
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KenDiriwan

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You be surprised how k-car dominate domestic JP market for casual usage. It's all about efficiency for daily purpose. And even more choices in Autobacs for k-car.
 

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