Another way to think on this...because fankly I don't know that you're already on the limiter like I was before starting to mod my ski...
Lets say you're seeing 69mph @ 8100-8150 on an other wise stock ski and oem speedo/tach read out. I'd say you're on the limiter.
But what if you are seeing 68mph @ 8000. I'd say you aren't on the limiter and will see immeadiate improvement from just an air intake imrovement.
See?
You really need to log all data before, during and after you test. It's very difficult to advise someone without knowing specifics such as air and water conditions...fuel load, oil level, weight of driver, altitude, barometric pressure, relative humidity.
All these factors come into play especially when you start adding bigger wheels, external intercoolers, fuel injectors, fuel regulators, set back pump mods ect.