The plot gives an insight of how Petty Enterprises started and how Richard became the king. It was told from Lee's point of view and of course Richard played himself.
Yes, this was made on the cheap and you can clearly see Richard was uncomfortable with acting. There were many composite characters that left me a little confused. But I found it enjoyable not only because I have been a Richard Petty fan for forty years (in fact I met Kyle and he's one of the nicest guys you'll ever meet) and Darren McGavin nailed Lee Petty's character down pat.
Yes if you been a race fan it is kind of a fun little movie to watch. But it was too early because Richard was at the zenith of his career at the time, and it wasn't about Richard as much as it was about Lee. But if you want the real story might I suggest Petty Blue.