Gee how could I have forgotten to include Troy Ruttman as a top 10 Roadster contender? He won in '52 when very young driving a stretched dirt car after Vukie had led most of the way in the first Offy powered Roadster.

Neville, in addition to the 4.2 Offy 4 and the Novi V8 there was the Sparks 6 cylinder engine which seemingly was an Offy with 2 extra pots. A 183 c.i. (i.e. 3 litre) supercharged Sparks powered the winning car in the 1946 Indy 500 but then from 1947 to 1965, the Offenhauser ruled. By 1949 there was only one Sparks powered entry and none afterwards.