Really fun entry, had some AWESOME music, good job!

The artwork is good and the driving/drifting felt really good (at least in the starting gear). Overall wonderful job and keep up the hard work!

Recommendations:

• Switching Gears - This was quite frustrating. If you intend to keep this game based on a single input (LMB), you can try letting the player double-click to switch gears/boost.
• [R]estart Button - Many times, I would try to change gears, only to be blasted in the wrong direction. Having a restart button would have helped make this a little more manageable. This also shouldn't conflict with the theme since the Restart button has no gameplay influence.
• Checkpoints - These need to be large enough to cover most of the lane. If you emphasize "short cuts," then this actually hurts the game quite a lot. You should never give the player a path that would prevent them from meeting with a checkpoint, instead create shortcuts that diminish the time between checkpoints and force the player back into the lane.
• Level Progression - If you have to unlock levels, please save that information; otherwise, just make all of the levels available from the start. There's no reason to prevent the player from checking out level 3 even if they were unable to complete level 1/2. It is just a game jam, let everyone see how much work you put into it!

It has a lot of stuff that I like but I think you might have been trying to do a little too much for the limitation. Switching gears was a bit of a hassle since it turned my car around sometimes while trying to mouse over the new gears. Sometimes it felt like it just changed gears without me doing anything. On the first level, some of the cacti peak out over the tops and bottoms of the walls, make them hittable. I'm pretty sure I won my first race, but I guess I didn't hit all the checkmarks so it said I lost. I'd be nice if there was some feedback to the checkpoints so I knew I'd hit them.

The art was mostly good, but not always consistent. It feels like with a little more time, or with less limitations this could be really cool.

Not the most creative idea but you implement it really well! I love the graphics and the music is fantastic! Great job!

Ooh cool game! The music was just the right amount of stress. 

I made a driving game too if you want to check it out.

Nice game. Really enjoyed it

the art is good but it is not that easy to press a different pedal while steering

I really like it its really fun there were a few bugs here and there but nothing to big but nice game. if you don't mind checking my game out feedback would really be appreciated.

Really cool game, love de music and the art style! There were a few bugs, but nothing that bothers the gameplay, great work!

I like your idea.  Good job.

Nice little game. I liked the art, and the music was quite catchy. I would suggest adding timer before races start, and also walls' colliders at some places are too high and because of that I got stuck out of nowhere. Overall game felt good and it was fun to play, well done!

Really nice game, though the UI was a bit buggy

There are some issues with the UI but the game was really fun overall.  Good job :D

There were a few buggy artifacts here and there, but overall it's a really cool game!

A bit buggy. Oh well, that is why i do not trust gms with HTML XD 
But other than the occasional bugs it is okay~

Cool and fun game, the timer was off-screen from some reason but I had a lot of fun, I like it, good job