Four round tailights? Not many cars with Four rounds anymore with black outlets near/under the lights. The first one that comes to mind is the Scuderia.

Then the GT-R?

If you were in Germany near the Ring I would say maybe you ran across an earlier stage development model of the 2014 Vette, which would nearly fit your description to a "T".

 

Perhaps if you could explain the note of the engine? V8 roar and rumble, screamer like a V10...