Hazen91

I have a 96 gsx with the 787 motor in it that we bought at the end of last summer. it has several aftermarket items such as intakegrate, reduction nossle, factory pipe, and a few others. I have only had it to the lake a few times but the second time we took it we put it in the water and it would not go any were it would barly rev over idle. after a minute or two of keeping it pinned it will finaly get power and take off but as soon as you would let off for a couple of seconds it would do the same thing. It also will not idle on its own and will end up dieing .but out of the water it will rev and idle fine. I have noticed that out of the water with the water hose hooked up and it running some oil will come out of the exhaust.I have changed all the grey fule lines cleaned the carbs and rave valves checked the compression in both cylinders and they both check out fine, any ideas?? Thnx