so here's my recommendation, but other may have more experience...I'm going off of what has worked for me on my ski, but my engine is a bit different and I don't ride in surf. My guess is that in surf you really want instant hard pull in the mid rpms and not the absolute bottom, as I'm guessing that you tool around faster and have more of a wave ramp to launch off of than us flatwater guys...So, if that's true, I would do this:
- 771 with port work (contact Jetmaniac on here)
- good ignition (I prefer the Epic, others might not)
- ADA girdled head with domes for 93 octane
- is your exhaust a Factory Pipe b-pipe? if not, do that. Bottom screw open 3/4 turn, others closed.
and, assuming that, I'd get a Solas mag pump with a Skat C+75 big hub impeller, probably a 12/18 or 13/18 pitch.
Again, that's just my guess. For a real professional opinion, you can't go wrong by talking to Dave at Impros.com.
Hope that helps...