Accent CRDi ayaw mo bro? 768k SRP for the base M/T variant. Very easy to squeeze more power without having to spend too much, and will still give you good gas mileage. You also get the bonus of added safety features like driver's airbag and 4 wheel discs with ABS.

Or if you want to fiddle around a lot, maybe you'd prefer the new 1.4L Kappa Accent 6MT. With the lower purchase price, you get more budget for mods. The 1.2L Kappa Rio had great reviews, so this one should be better. You'd probably be focusing more on the suspension with this though.