Great!
I loved it! It reminds me of a lot of the extreme racing games with loopy tracks. Id love to see more and longer levels now that I am done with the tutorial.
I think the bonus things and doing tricks should take more off of your final time, right now they are only worth getting/doing if you have the opportunity.
I also think it would be cool if different car colors had different dynamics: one jumped higher, one accelerated faster, one had more down-force, ect.
Good basis for a sequel?