a 91-98 nissan 240sx.....can be as low as $2000 for a shell and $10k for an rb25/26DETT with everything to get it installed by a pro and enough hp to outrun most stock cars, and it doesn't throw off the weight balance that much so handling would be the same.(or you can stay with the stock engine and turbo it, which can still outrun some stock cars that run 12s), upgrade some suspension parts and brakes(300zx slotted brakes are a good upgrade) and you can outhandle most stock cars, and still be under the 20k budget(with some leftover to go to legal race tracks). other options would be a used mustang GT(most years cept 05 and special models), SRT-4, a na supra, rx-7.....list goes on and on for 20k.
a Golf GTI sounds good too, like they're sayin on above posts.
1993 nissan 240sx hatchback(stock) <<drifter, straight liner, road courser
"Horsepower is the force that determines how fast you hit the wall. Torque is the force that determines how far you take the wall with you after you hit it."
"Horsepower sells cars, torque wins races" - Carroll Shelby
"Real cars don't make power at the front wheels....they lift them."