Desmodromic type valve actuation.?
Answers:
Mercedes-Benz
http://en.wikipedia.org/wiki/mercedes-be.
It seems that Delage were the first to use desmodromic valves on cars in 1914. The design became better known after Merc used it on the W196 GP car in the mid 50's. Many others had used it, including Peugeot and Ballot, on racing cars well before Merc tried it. There are likely to be more modern applications that others can identify.
Velocette used it on 350/500 viper in the 50'S
Alfa Romero used them in the spectacular engine for the Montreal. It was a V8 and there were no belts or chains anywhere in the engine. Everything was done with gearing. Was a real ***** to work on but something to see and hear when at full song.
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