I think if you want more...just up the @.050 8-10 degrees.
It's a success for the small cam used.
I do believe there is a 560hp 540 tq combo out there...and it's right nextdoor to this build.
or even 20 more degrees.
I ran a 260@50 cam on my stock stroke 360 street strip car.
Swapped it into my current 418. IMO on 418 inches to me 260@50 is marginal, and leaning more street than strip.
What he has there could handle lots more camshaft and still be streetable while being more potent at the track.
That all said, it makes good dyno power as is. Be curious to see it go down the track and hang some numbers on a scoreboard. Should run well into the 10’s