The old cars from the 50s are so much part of Cuba imaginary that many tourist guides display one on their covers. I confess they were one of the main reasons why I wanted to go there. But I never expected they would be so "alive"!
In my own statistics, about 20-25% of the cars I saw on the island (but in Havana can be almost 50%) are classic American cars (Cadillac, Chevrolet, Bruick, Ford ...) dating before the revolution (1957). And the rest is about Russian Ladas from the '70s, Polish Fiat 126s from the '80s and French cars from the '90s (and just a few dozens from the 2000s). It must be said that traveling by car is a privilege for Cubans. Apart from hitchhiking - even on the motorway - horses are perhaps the most common mean of transport for the average Cuban, riding, or with small gigs or carriages. As amatter of fact, due to the shameful embargo, Cubans for decades have been forced to adjust to the little they have, a huge injustice. This is an additional reason to respect this people and praise their creativity. For a foreigner, instead, it is the chance to travel back in time.