As most of the demand for automobiles was for taxis in the early 1950s, the Toyopet Super was specifically developed for that market. To withstand heavy use on the still prevalent unpaved roads, the chassis came with a ladder frame as well as rigid axle leaf spring suspensions for the front and rear, which provided truck-like sturdiness. Since vehicle categories were revised earlier and the maximum engine displacement for small cars was raised from 1,000 cc to 1,500 cc, Toyota developed a new 1,500 cc Type R engine and fitted this onto the Toyopet Super. The engine delivered a maximum output of 48 hp, which was 21 hp more than that of the 1,000 cc Type S engine. Powered with this new engine, the Toyopet Super's performance became as good as that of imported cars.

The coachwork of the Toyopet Super was executed by outside firms. The body produced by Nakanihon Heavy Industries (today's Mitsubishi Heavy Industries) was the Type RHN (N stands for Nakanihon), whereas the one with the body manufactured by Kanto Auto Works was the Type RHK (K stands for Kanto). Both models earned solid reputation as taxis, becoming the top-selling models of Toyota.