Re: Evinrude lark
They only made a 35hp Lark from 1957-59, in 1960 it became a 40hp. The '57 had a clamshell cowl, sort of the old egg-shaped style. 58 and 59 was a one piece cowl and more squared off. If it is indeed a '50s Lark, 24:1 would be correct.
