Normally, the differences are usually in the electronic calculator software, due to the issue of anti -antamination regulations, (ignition cutting regime, co a idle ...).
Another difference is usually in the butt due to the limit compression ratio so as not to chop, in North America gasolines with an octane index inferior to Japan are used, so it is possible that the American engine has some less compression and the rod chop sensor is \ "more sensitive \" in the case of driving with the Japanese motor by North America.
But come on, this are assumptions because if I tell you the truth has not been appropriate.