I don't know what I was smoking each time I fucked up the wins/losses/games remaining. But...
The Astros have 23 games left (the WAS series is 4 games, and I completely overlooked October's denouement against the Cubs). At 66-73, they need 15 wins to get to .500, i.e. no more than 8 losses.
15-8.
For their previous 23 games, the Astros are...15-8.