Hey SD; thanks for all the comments, much appreciated. Hopin Brett will chime in here; My 2002 is the same step as your 03.
My slip is like 21% with my 26" and 20% with the 28"; if I can get these down to a reasonable # then I'm off to the races..And we checked my tach when we were ensuring engine was running properly and all seems good, yesterday was setting off the alarm when I was in the 5500 range so all seems good..

Just an FYI. Peak power is right at 5200 with the 103 kit. It drops quickly past that. So, you need to prop for 5300 at the most with ideal conditions, light load. It will drop a couple of hundred when loaded with people and fuel.

Give you some base numbers

my 2001 27 Fever 500efi rh 25 Hydro 5350rpms gps 74 all day long.

same set up swaped to a Hydro 26 got to 76mph on gps 5300rpms, WAS A ***** TO PLANE OFF, back to 25 hydro.

See if you can borrow a 25 Hydro at 5500 rpms youshould be knocking on 78mph???

thanks Tampa; is yours a step hull? like to try a hdro, which model of prop are you suggesting? Thanks

Thanks Bob, I believe you did one of these installs that same as mine?? Dana, Raylar 103 and ECM recurve from Ray; do you have the dyno info??Also yesterday my water temperature light came on, do we require a lower temp thermostat or is that part of Raylar's kit? Pete

Water temp should not increase. You run the stock t-stat with the standard kit. I'm attaching a dyno run we made with the 103 kit and Dana's. This engine has a Whipple stage 2 program and requires premium fuel. The boat is still running great.

Bob

Petesflht, I installed a raylar kit in friends 05 29 fountain which ran 65mph stock and 74 after installing kit! We ended up dropping drive hieght 1 inch to improve slip with a 28 bravo one non lab at 5300 rpm 1.65 ratio drive. dropping drive improved plaining and mid range slip and actually went 2mph faster on big end. 5 blade probly would of worked also?

The ones I used were Quad 4, yes both boats single step, I don't think the 27 hull changed really at all from 1995-2007? Doesn't matter that much for top end anyway, look at a 27 running 70+ only about the last 3' are in the water, step is not even being used over 70.