Before the handwringing begins over the Canadian (N.A.) 451's 70 HP vice the advertized 71 HP, the 71 is 71 PS ("PferderStarke": German for "horse strength"), or 71 CV ("Cheval Vapour": French for "horse steam"). PS or CV are "metric" HP units as used in the EU, Japan, etc. The Canadian 70 is SAE (International or British HP). A unit of PS or CV is a slightly smaller unit than SAE (about 1-1/2%), thus 71 PS = 70 SAE.
BTW, "BHP" does not mean "British horsepower;" it means "brake horsepower" as derived from a brake dynamometer.