What size BBC did you install, 454? I've been thinking bigger carb trying to find someone with one I can try before I buy> Thanks for the heads up.

yes I have a 454 that was bored 30 over and stroked to a 489 merlin iron heads and comp hyd roller cam pushing 530hp on dyno. I do have a holley 750 or a edlebrock 750 that I would sell you if interested which would be plenty for your motor.

InstaGator:
If that is just a freshened up 330hp 454 using the stock 330hp camshaft then I believe the max operating rpm should be ..4200-4400 ..Bigger carb may net you a few more rpm but I doubt enough to make a difference.. 330hp isnt a lot of power for a boat that big and heavy.. Stinger 260 is a lot bigger than a normal 26ft sportboat. Fully loaded Im betting your close to 6000lbs.