A mid 1930's Buick straight 8 I worked on a long time ago had a manually-controlled heat riser valve with linkage on the steering column. Lots of small aircraft engines have the same sort of system to prevent carburetor icing under certain flight conditions.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!