Car trades and track tirades

Here is an interesting question for the masses:
If one buys a legit car for $500 but finds someone who values said car highly and will trade the $500 car you own for something that could be worth more than $500, would the new car still be valued as $500 car?  Would you incur the judges wrath?  Would it enrage the populous?  Would crushinating ensue? I only ask because this situation is about to be presented to me and the car I'd trade for is, well, a possible LeMon's halo car that would earn us instant fame and fortune on the track.  Or instant hatred and cat calls of BS.  No it's nothing new like a SE-R or an SRT-4.  In fact it's decades old.  A classic, one could say.  So, what do you guys think?

PS:  No I won't tell you what the car is because I finally want to play the *redacted* game and have everyone guess.  I encourage your guesses though.