276HP - Magical Number?
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- Paganisterr
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The Japanese have a "gentleman's agreement" that all cars they make are to be a MAXIMUM of 280PS, which translates to 276bhp. This is why you never get overally powerful standard Japanese cars as they're all at that limit. Now though, it seems they are thinking of breaking the agreement to make more powerful cars as 280PS just isn't enough anymore.
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- JDA1982
GT is correct, it's an agreement made by the manufacturers to prent them getting into power wars and such. However the areemnet was dropped last year so that they could build cars to compete with European and American sportscars ect that are more powerful.
Scaff
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Also even when the agreement was in 'force' it was very loosely applied by most manufacturers.
They would be quite happy to say that a car was only developing 276bhp, when the actual cars being produced were at times developing much higher outputs.
You can see this in GT4 when you buy certain cars and the 'showroom' figure is 276bhp, but as soon as you get them to the garage the output is higher, sometimes much higher.
Regards
Scaff
They would be quite happy to say that a car was only developing 276bhp, when the actual cars being produced were at times developing much higher outputs.
You can see this in GT4 when you buy certain cars and the 'showroom' figure is 276bhp, but as soon as you get them to the garage the output is higher, sometimes much higher.
Regards
Scaff
- 860
I remember when I bought my TT Supra RZ......276hp showroom......330hp in the garage......BEFORE THE OIL CHANGE!!! I was like.....ZOMG.......WTF???
And then it's the same story with R34 Skylines and TT RX-7 and Z32 300zx TT
They are all at 276 showroom and 300+ in the garage...lol. Reminds me of the muscle car wars when they were underrated by like 50-100 hp and torque. lol Of course that was for insurance puroses
And then it's the same story with R34 Skylines and TT RX-7 and Z32 300zx TT
They are all at 276 showroom and 300+ in the garage...lol. Reminds me of the muscle car wars when they were underrated by like 50-100 hp and torque. lol Of course that was for insurance puroses
- 3,746
When the last Supra was being advertised in the UK it was quoted as having 330bhp. AFAIK it was exactly the same as the Japanese car, so that gives you an idea how underrated some of the cars were - roughly 55bhp in this case.
@gOoSeTeR: http://en.wikipedia.org/wiki/Horsepower#PS
@gOoSeTeR: http://en.wikipedia.org/wiki/Horsepower#PS
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amp88
The UK car had a larger intercooler and ceramic turbos, and was rated at 326hp. The JDM car was around 290/300hp, though rated at 276hp.
Almost none of the manufacturers stuck to the agreement, except Honda - whose NSX was hamstrung for a decade as a result. They all said 280PS, but even the Imprezas were running nearly 300.
Pink_the_Floyd
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This rule only applies in Europe, I'm not sure about other countries though. When you're in Japan, you'll find the cars having 280-330 HP. Most people think these cars have the rule in Japan but it's just not in Japan. You'll buy a Supra in Europe with 276 HP, if not imported from Japan but you'll buy a Supra in Japan with 330 HP.
But this rule has been deleted now as Nissan is the first to build a 3.0 V6 450 HP sportscar (GTR/Skyline R35?)
But this rule has been deleted now as Nissan is the first to build a 3.0 V6 450 HP sportscar (GTR/Skyline R35?)
Scaff
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Pink_the_Floyd
No it did not just apply in Europe, the 276bhp limit was am agreement between the Japanes manufcaturers not to sell cars over 280ps to the public.
The agreement was a direct result of pressure in the Japanese market place, and was only between Japanese manufcaturers.
While this has some impact on cars exported around the world, it was never a leagl requirement and certainly never intended for Europe (or any other market). Hence the reason Mitsubishi in the UK has long sold cars with power outputs well in excess of the limit.
Regards
Scaff
Pink_the_Floyd
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Woops!
*Looking at a Norwegian car selling website, realising none of the Japanese sportscars have 276 HP or even below*
*Looking at a Norwegian car selling website, realising none of the Japanese sportscars have 276 HP or even below*
- 30,037
- Cuddington, Cheshire
- JDA1982
Doesn't make the end product any better though, more power isn't always the answer, and the gentlemens agreement has arguably taught some Japanese car makers invaluable lessons on how to hone a cars chassis to make up for the power loss. At the end of the day, th eJapanese manufacturers deid what they thought was best for the industry, and it was going well, but the time has come where to compete with European and American cars who have upped the ante performance wise, they can't contain themselves to that 280ps limit anymore.
Interestingly enough, I know of at least one excellent example of an American company under-rating their horsepower. The Buick Grand National was rated at 275 hp but based on its incredible speed and acceleration it's clear that it was probably well over 300 hp.SirBerra
One trick is to use wheel horsepower (whp) as the official rated number. whp is 5-15% lower than brake horsepower (bhp), the standard that nearly all cars use. I'm not sure if that would fly anymore, at least in the US, since the laws were recently changed to require every automaker to rate their cars in the same manner. But I bet they did that all the time with those gentlemen's agreement cars - a listed rating of 276 hp probably meant something like 276-280+ whp, or 290-330 bhp.
I like Germany's agreement better. VW/Audi, Mercedes, and BMW all have 155 mph speed limiters on their cars, but they can throw as much power in them as they want. And savvy customers shouldn't have trouble removing the limiter, though exceeding 155 mph isn't something you would do that often, even in a super-powerful German grand tourer.
It's unfortunate because now that the gentlemen's agreement is basically finished, sports cars aren't that popular anymore. Right as the agreement falls apart, you have Toyota discontinuing ALL their sports cars, no more RX-7 (the RX-8 is hardly a worthy replacement, nice as it is), no more 300ZX TT, no more 3000GT... it's too bad.
- 74
There are some cars still alive though. S2000, New GT-R, 350z, and uh...ya ur right they are going away
- 1,020
In Europe we used to do it the other way round: Maserati would brag that their XYZ had 330bhp when it actually had 280 
Then of course there was the E-type, the world's first independently tested 150mph production car provided you got the works race engine and the special gearing that handily appeared on all the press cars...
Then of course there was the E-type, the world's first independently tested 150mph production car provided you got the works race engine and the special gearing that handily appeared on all the press cars...
- 112
Luca
Drivetrain loss is alot more than 5-15%, even on a FWD and it only goes up on a RWD or AWD.
Famine
My USDM Evo 8 dynoed at 226 HP (at the wheels on a 4WD dyno) when stock. Factory rated at 271 HP, so that's only a loss of 45/271 = 16.6%. Either the 25% number is way off (at least for the Evo), or the 271 HP claim is underrated. I'm inclined to believe a bit of both...
In its current state of tune, the car dynoed at 323 WHP, and the tuner estimates the BHP at about 390, for a 17.2% drivetrain loss. I'd love to believe the 25% lossage number, since that would put my car well over 400 BHP.
Speaking of Evos, although Mitsu always stuck to the "advertised" 276 HP number, later Evos (Evo 5 through the present) have certainly exceeded that by a noticeable margin. Finally, with the Evo 9, the advertised number exceeded the 276 HP mark, marking the end to the "gentleman's agreement" with respect to the Evo.
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jbrennenMy USDM Evo 8 dynoed at 226 HP (at the wheels on a 4WD dyno) when stock. Factory rated at 271 HP, so that's only a loss of 45/271 = 16.6%. Either the 25% number is way off (at least for the Evo), or the 271 HP claim is underrated. I'm inclined to believe a bit of both...
In its current state of tune, the car dynoed at 323 WHP, and the tuner estimates the BHP at about 390, for a 17.2% drivetrain loss. I'd love to believe the 25% lossage number, since that would put my car well over 400 BHP.
Yes, it's very much rule of thumb. Some standard, agricultural 4WDs can push the losses as close as a third of the crank power. Imprezas are pretty much dead on 24% until you play around with things. Overpowered FWD cars with LSDs can run up to 20% losses...
Besides, it's only the power-at-hubs that matters. 250hp on the road is 250hp on the road, whether or not you need 250hp at crank or 350hp at crank to get it there.
Scaff
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jbrennen
In the US maybe, but here in the UK they have quoted figures well in excess of 276bhp for quite a while now (I think the EVO VII was the first in the UK to publish real figures with the Evo VII FQ-300 in 2003) .
Including the Lancer Evo VIII FQ-400, pushing out 400bhp and Mitsubishi in the UK were quite happy to publish the correct output.
Regards
Scaff
Famine
You and I know that. Maybe someday the car industry will figure that out...
But I suspect that they like it the way it is. I could imagine that if they advertised wheel horsepower numbers, you'd have a bunch of new car buyers going straight from the dyno to the dealer complaining that their brand new 230 HP car just dynoed at 226 HP, and complaining that they got a lemon.
At which point the car dealer could:
- Change the oil, putting in 0W20 oil. Thin oil -> less power loss.
- Inflate the tires on the drive axle(s) to about 44 psi. Less power wasted in flexing the sidewall.
- Dyno the car in an air conditioned room. Cold dry air -> maximum power.
And voila, the car now dynoes at 235 HP.
But better to avoid the whole thing, and advertise HP numbers in a way that can't be easily verified.
- 112
We also have to remember the difference between inertial load dyno's and constant load dyno's.
The inertial load types will give different values based on what gear you are in; the constant load types will give almost exactly the same value no matter what gear (higher gear will give read more power because the inertial acceleration is spread over a longer time). Also the inertial load ones will show a great power loss for AWD because you are accelerating more mass than on a 2WD dyno. You are spinning 4 tires, wheels, axles, brakes etc. on an AWD dyno on the 2WD dyno you are only accelerating 2 of each. (In real life you are also accelerating the non-driven wheels/tires/brakes by road contact)
Most tuning shop dyno's are the inertial load type; I'm not sure what type the engine OEM's use.
Also you must remember that the XX% loss is not constant with rpm, gear, and total power. The losses in your drive train come from many sources: inertial loss (when accelerating), viscous loss (tranny/gear fluid), gear mesh loss, bearing friction loss, etc. Each one of these losses is non-linear and will change with gear, rpm, and power level. In general it is safe to assume the % loss goes down as hp goes up. So a 100-crankHP car might be at 20% loss (20 hp), that same car with the engine at 200-crankHP might be at 15% loss (30 hp). The raw HP loss always goes up but the % often goes down.
The inertial load types will give different values based on what gear you are in; the constant load types will give almost exactly the same value no matter what gear (higher gear will give read more power because the inertial acceleration is spread over a longer time). Also the inertial load ones will show a great power loss for AWD because you are accelerating more mass than on a 2WD dyno. You are spinning 4 tires, wheels, axles, brakes etc. on an AWD dyno on the 2WD dyno you are only accelerating 2 of each. (In real life you are also accelerating the non-driven wheels/tires/brakes by road contact)
Most tuning shop dyno's are the inertial load type; I'm not sure what type the engine OEM's use.
Also you must remember that the XX% loss is not constant with rpm, gear, and total power. The losses in your drive train come from many sources: inertial loss (when accelerating), viscous loss (tranny/gear fluid), gear mesh loss, bearing friction loss, etc. Each one of these losses is non-linear and will change with gear, rpm, and power level. In general it is safe to assume the % loss goes down as hp goes up. So a 100-crankHP car might be at 20% loss (20 hp), that same car with the engine at 200-crankHP might be at 15% loss (30 hp). The raw HP loss always goes up but the % often goes down.
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