38 on the gps is the best I have seen with 2 people and full fuel. Probably could have eeked out a couple more mph playing with trim. The 190 hp version and different prop should do a little more.
I've gotten my 85 cuddly 170 up to around 35 WOT and it cruises at around 25 at 3000 RPM. I don't think it's ever been rebuilt - I redid the head 10 years ago just after I got it.