Yet conveniently a few days later he has a breakthrough....without spending any money, risking his life or doing work to his car....
It's ok to be a fanboy but don't be blind to the obvious either.
It sure is easy to think like this after the events. This is why hindsight is a word. It's even overexplained in the story that he doesn't think he'll get immediate money from his project so, desperate times call for desperate measures. I don't think anyone believes that going for the racing angle is the smart thing to do, but hey, hindsight again. Also, the breakthrough happened a bit random and it wasn't something he expected, so .... hindsight yet again.
Maybe you didn't have any events in your life that forced you into stupid rash decisions, but things like this happen all the time in real life. People desperate going into debts with money sharks, or wasting even more money on trying to win at poker/gambling/other things. Saying this particular plot is absurd (your words) is ...absurd

) when there are thousands of things like this happening in real life. Sure, maybe not specifically car racing, because it's pretty niche and few ppl have a car that can race or they even have the skill to do it. Even smart people make bad decisions when faced with emotional trauma.
And now to poke some fun back at you "It's okay to be a hater, but don't be blind to the obvious either"
