Q: Will people pay money for a Holden HJ Premier equipped with a Dictaphone, a small fridge, and a 13B rotary engine?
A: Hell no! (But Mazda tried to sell it anyway.)
In the 1970s, Mazda was a small company with large aspirations. In the domestic market, Diet members and captains of industry were being driven in Toyota Centurys, Nissan Presidents, and Mitsubishi Debonairs. Mazda wanted a flagship sedan, but it didn’t have the money or time to develop one by itself.
Mazda needed a tried and true right hand drive platform. The pickin’s were slim, and Australia’s Holden HJ Premier was chosen. The longer HJ Statesman could not be used because it was badge engineered and sold in Japan as the Isuzu Statesman De Ville. (Has your mind blown yet?) Given that the average Japanese man in the 1970s was probably a foot shorter than the average Australian man, the wheelbase difference was irrelevant.
CKD kits were shipped from Oz to Hiroshima. The venerable 13B rotary engine was thrown in, the seats were re-upholstered, and a fridge (in the trunk) and Dictaphone (next to the back seat) were installed. Over its four year lifespan, Mazda sold 799 Roadpacers. 799.
Why did it fail? The list begins and ends with the poor engine-body pairing. The 1.3 liter Wankel produced 135 hp, as much as the Holden’s 3.3 liter-6 in the Australian market. But the tiny engine has to be revving at 6,000 rpm to reach the peak (versus 4,400 for the six cylinder). As for torque, the story is worse. The Mazda produced 135 lb/ft at 4,000 rpm, the Holden produced 194 lb/ft at just 2,000. Coupled with then-new emissions control technology and a 3-speed automatic, the Roadpacer was painfully slow. The V8 President and Century blew it away. Oh, and the Roadpacer could barely get 10 miles to the gallon in the city. End. Of. Story.
Here is an excellent video tour of the Roadpacer, in Australian.
This is a detailed look at assembling the 13B at a plant in Hiroshima.
Information sources: June 1975 issue of Wheels and Japanese Wikipedia.