Tony, you are right. According to Tim Slade's reference, book, the big difference on the 112 chassis vs 111 is the air suspension. They all had it regardless of engine. I suppose in theory one could exist, but the only V8 air-suspended cars were the 300SEL3.5, the 300SEL6.3, and the 600. Others have been built (KM has done several) but not as production models from the factory. The 3.5 engine came along after the 112 coupe was no longer in production anyway, by a few years I think.