Hmm I might have everyone beat as far as cars I've "owned and raced" for the past "one" year.
415-->Yokomo BD-->EvoIV-->TA05-->FK05-->415MSX-->Surikarn Cyclone
So far I have sold the 415, Yok, and FK05. The longest car I've had and still have is the EvoIV... goin on 2 years. Great car, but the EvoV is coming out next month..