I got one of the 346cc preditor engines settin on an all aluminum frame LT i built and its runnin up to 3500rpms or so and dooing the sergin up and down thing if i try to go passed that. What do i need to do,,,, id like 4k or maybe 4200 out of water

I heard you can easily get those things up to 6000 or so. Go find a go cart racing forum and you should find what you are looking for.

Try a Stronger governor spring

can i just disconect it?what other prpose does it have,,,i see that one end is connected to a lever that goes down into engine

you can disconnect it but you run the risk of over revving the motor. You may be able to put a coil from a new Honda on it I think most of the newer GX engines have an internal 4700rpm limiter built into the coil (are the predators clone motors?). Or you can adjust the tension on the governor spring to get the right rpm.

i can limit my rpms by simply ajutsing throttle linkage for right rpm in the water,,,,im runnin an 8x4 beavertail prop and not able to get up passed 3650 after cheating the governer.. if i run it up out of the water it will blow up over 5000,,,,,its 11 or 12 hp do i need a smaller prop,,,yes its a clone