You mean this?
Dyno's vary by type and even individual machine configuration / calibration, how well its been maintained, and operator error. 290 on a dyno jet might be 240 on a dyno dynamics, 300 on a dyno pack, or 230 on a superflow and so on. It's at best a guide.
The only guaranteed data point is the manufacturers published hp start point when it left the factory.
Anyway arguing hp numbers on a forum is as old as time, I know what I have and I'm happy with it for now 😁