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The Hindustan Contessa, because that was the only prototype we did from scratch rather than rolling over a EU chassis. The Amby was rolled over from the Morris Minor chassis btw. And that car could REALLY haul roads....and the only thing which held the Contessa back was the underpowered 4 cylender Isuzu. If there was a V8 integrated into that engine, that Contessa would b feasting on a bunch of imported entrials for breakfast.
I nominate the HM-C because of its originality (only chassis to be designed from scratch in India vs rolling over older chassis) & the fact that if configured properly, it could REALLY rule the road like a General Lee!!!!