The rules for a sport car in my opinion is convertible, manual gearbox, low to the ground and very small and feel like it is fast.
Honda S600 was almost perfect as the problem with 90% of cars are they feel slow at the speed limit, but not so the Honda, you had to wring it out in every gear just to get to the limit and it felt like it was doing 200kph when doing 100kph. Pity during the time I owned it I spent 90% of the time fixing it and only 10% driving it.
