Neat little racing game! :D I always enjoy such top down racing games. The upgrades give them a nice veriety. It's actually really challenging to drive well - I only won the first race. It could use some indicators when and what turns are coming up, especially for driving a map for the first time. Also I'm not sure, if the drifting is any useful as it seems to only make the turns wider. But other than that this is a solid and polished game. I'm especially impressed with how well the enemy AI adapts to all the bumps and shrinking rays I attack it with.
Good job! :)