Tracker 90 HP set up

[Cojab]

I have a 98 Tracker PT 185 with a Mercury 90 hp. Current prop is a Mercury Laser II 22P
Bought this boat a few years ago and hasn't seemed to rev up the way it should. I just replaced my tach because it was bouncing around all the time and I didn't trust the readings but now they should be good.
I am only getting a max of 4400 RPM and a top speed of 32 MPH. After verifying this today I came home and checked a prop to pad measurement.
From the measurements I took it looks like my prop to pad is 7 3/8". (I got my directions for the measurements from Steve's Custom Props website)
The engine is mounted on the second from the top holes.

So I imagine I need to raise the engine considerably. Would the low engine height be the cause of the low RPM's?
What other characteristics would the low engine height cause?

One other consideration. I am outside of Denver Colorado so I am running at about 5500' of elevation. I am taking a trip to Table Rock in about 2 weeks and was hoping to see what kind of difference I would get from the elevation change. Table Rock is about 1000' elevation.
Thanks for the help.

[moecarama]

I have the same rig but running a 21p prop and get 5500-5600 rpm @ 42mph loaded 39mph. The engine is mounted in the second hole from top.

[Cojab]

Thanks moe. Thats exactly where I would expect I should be running since the engine says max RPM is 5500.
I'm not really concerned with speed since I'm not a tournament angler and most of the lakes around here are small but I want the boat performing as it was designed.

[11pounder]

You need to drop to a 19 or 20 inch prop.

[mdtritn21]

18" or 19" prop at 5500 ft because your losing 20% of your HP due to altitude. Don't expect to run what moe runs but maybe 37-38.

[Cojab]

Thanks for the info.
So the prop to pad measurement isn't too big of a deal here?
Also, I suppose I should see a pretty noticible difference when I go to Table Rock?

[Cojab]

I am going to Table Rock next week with the boat and I am going to try the 22p prop at that elevation to see what it does. I am also taking a 19p alluminum with me just in case.
I will try the 19p when I get back also to see what I get and follow up.