by the way, the engine they use in the Q45 in Japan is Direct Injection, so it has more torque, but lower hp rating, sure they lower the output also.
It's not magical, but it is funny thing that country that produces the car doesn't get the more powerfull version.
no, It is the ministry of transport sets that gentlemen's agreement, that is 206kw-280hp for all cars, so that it is safer, and such and such, there are about 10000 deaths each year from car accidents in Japan each year, and you can see why now.
And there are some exceptions, like some after tuning company sales, such as NISMO, Autech, ...etc,(for nissan)
but the point is that all those engines have the ecu management that restricts the fuel and the air so that the engine will not make more than 280(about), even though many companies lie about that(Subaru for one) and funny thing is, there is absolutely no restrictions for torque.
I forgot exactly what car made this gentlemen's car, but I believe that was some Nissan car, 300ZX, maybe it was Mazda Cosmo(correct me if I am wrong). but one of the car caused this to happen for some reason.
I really believe this will be changed as far as I am concerned, as all new cars are coming out in Japan right now. Soon enough, one car will break the 280 rated hp, and will be okay. The thing is that standard of safety has advanced so much in last 12 years(that is about when the agreement happend), so it should really be changed so Japanese cars are more attractive and powerfull.