Let me guess… engine block?
I’d say it’s less the money than it is whether you’re negatively impacting the durability and drivability to squeeze that extra 50 horsepower out. On the money front, eh, this is an inherently absurd hobby, I spent $2700 recently for my DOHC to make maybe 350-360whp tops? Yet I’m not particularly bothered by it because I like this engine and want to get the best out of it, yet absurdly I’m annoyed I bought a $30 set of centercaps for my wheels I don’t like and missed the return window on lol. This really isn’t a dumb or smart question but a philosophical one.