Lots of dough and ourageous speed and HP don't matter here. The trick is to make something that the masses can aspire to, that becomes beloved by owners and others, for it's everyday value and reliability. I am suprised that a Volvo 122 would initiate rudeness and yet a Datsun 510 not so. What is that about. Anyway the Datsun 510 was indeed a great 'affordable' car in the later sixties and had a good following back then and a jiant killer. So too now the Miata has proven to be a winner and being a sportscar may be timelss more easily I suppose like the MGB. So too is the Mini in both its concept and later itterations...a breakthrough design that changed everything and brought cars to folk who only had bicycles prior to. The Fiat 500 may well be one too and the 50s Lancia Aurelia in a diferent category. The VW is timeless in rear engine form.
There are others of course that many people could formulate a picture of in their minds but not most of the swoosh vehicles above. They would not even be recognised by most motorists even in their own time and who would know what a Mk. of Rolls even looked like or for most a Ferarri 250 GTO, or the distinguishing features of a Mk. of Mercedes. And yet the GTO would probably be iconic and timeless. All everyday cars can not be driven for many years; they age and become non-viable and are scrapped except for a very few. So that all that is left are memories of them and times when you were younger and pictures that you carry in your head. Few would even recognise most of the above posted photo's even a couple of years after they were made. That makes them irrelevant as well as not being timeless. Hmm I suppose the Mustang could be included. In a time when the Jellybean reigns I will not appologise for choosing one from the past that was not such. The 122.