bcarpman

I'd say that's too much total timing. Take care of that first.

What conditions are you measuring the water temp difference? part throttle or WOT?

CC247

It's when I'm on plane for about 30 seconds and then the temp goes up from 130 to 180 and climbing. i put the #76 jets in a 5.5 PV and all is well. I gotta stop foolin with it and run it like I stole it!!!

RumRunner

To see a speed change in a boat (by jetting) you'd have to be off by far to make enough difference. So you've got to Jet for wha gives you the best performance. One jet size which equates to about 4lbs of fuel or maybe 8 HP should not cause this kind of change ESPECIALLY this time of year. Put some more jet into so you don't hurt it in the fall when the weather gets better. The timing would also seem high, which can cause you to run lean without actual detonation.

CC247

RumRunner- thanks for the info. I recurved the dist. so now I get 35* total. The motor responds well to the 15* base timing. I also bumped the jets up 2 sizes from stock. #74 to #76 and it seems good. It doesn't surge and the cruise plug reading is showing tan color with alittle soot on the base of the plug. I don't have that many weeks left here in the cape before the snow comes, gotta go!! Thanks again