I think this might be one of StarStang's stories, but I haven't been able to locate it.
I'm fairly certain that the MC's wife cheats on him, and he drops her. He ends up falling for some big wig lady who is into car racing. Her father is the CEO of some huge company, and thinks the MC is beneath her. I remember MC feeling uneasy about the women's racing, because I think she said that she'd only sleep with someone who'd beat her in a race, and she drops everything to race anybody (but she never loses, except to the MC at the end).
Thanks in advance.