Regarding engine wear and loss of performance... do you think it works that way on the extremely rare cars? The cars that you can only get once and never again? That would suck if you wore out an engine on a unique car and were stuck with lower hp for the rest of the game.
Unless there's a way to "tune up" the engine to bring it back up to full power?
Unless there's a way to "tune up" the engine to bring it back up to full power?