Re: four winns 170 115 hp outboard
How big are the skiers and are they doing deep water slolam or just using two skis? I am 6ft/215lbs and *have* gotten up on a 67" slolam behind a 17ft bass boat with a 115 Merc, but I definitely had to drag a while to get up. The boat wouldn't plane until I got on plane with the ski which is a bad situation to be in. However, when I used a 72" slolam, I could get up without too much issue.
Using two skis, I have pulled people weighing as much as 240lbs up. So it's really all in who you're towing. I also never propped down to get a better hole shot, so that can always be done as well.
I'd say your fine unless you want to start getting serious with slolam/wakeboarding, but you should be looking at an entirely different boat at that point.