Entex was a company that reboxed other kits and created some pretty attractive box art. One of their more interesting kits was a visible Wankel rotary engine, which was a rebox of a kit available in Japan from Gakken. It hit the stores about the same time that Mazda came on the scene over here.
This Mercer Model was a rebox of an Aurora kit, in turn a rebox of an earlier company Saunders and Swader. If you search for the Aurora version, it can be found for around $ 100.
Several other models were sold in this scale by Entex, including a nice Model T panel truck. My own favorite is a Pendle Traction Engine, originally made by Bandai I think. But impossible to find.
Lindberg sold a 1/16 Stutz racer, which was also a Saunders kit. If memory serves, the original may have been motorized.