1999 Gtx prop help

[Jayr19912016]

Hi guys recently bought a 1999 gtx
recently had full engine rebuild. running premix too
Runs very well for its age but what I've noticed it's like its cavitating. At Wot ,revs fly up to 7000rpm and just dosnt seem to get out the hole like I think it could if it was setup right or with a better prop

All suggestions welcomed

Regards Jay

 

[Coastiejoe]

You need to look at the wear ring gap and the impeller itself. Also, if you have a carbon seal, that will allow for cavitation..