any adaptation that will fit the TH-350 should also fit a 200r4. the 200 has a shorter first gear than the TH350 as well as OD. not that you're probably going to care much about keeping your cruising rpms down.
and i'm assuming your dragster is going to be pretty light weight, so the 200r4 should be able to take it.
but I haven't heard much about them in race applications.
well, of course not. we've got 5.7L Chevys and Fords all over the place and big iron big blocks if we really want displacement. kind of tough for a 215ci to compete with that.
the Rover v8 stuff was developed a LOT more in Australia and Great Britain, where it was their domestic equivalent of a Chevy 350.
in fact, the Rover / Olds ( 6 head bolts per cylinder, 3.0L ) design has TWO Formula 1 championships from back in the 1960s. if you're interested in that, research "Repco". they're the ones who built the engines.
otherwise, the Buick engines saw a lot of use in boat racing over here due to the light weight.
the Buick v6 is also a variant of this small block design ( adapted from the Buick 300ci v8, so it has a taller deck ) and there was a ton of racing development done with that in Indycar, NASCAR and circle track back in the 1980s.
the problem with the Buick v6 in this discussion is that it has the standard BOP bell housing and is useless as a transmission source for you.
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