I am a proponent of the 1.5:1 gears.

I like the throttle response you get with the lower gear ratio especially staying in the 28-30 inch pitch range. I'm not talking about drag racing hole shots, but rather mid range punch is a great aspect. The HP/weight ratio will be fine as far as drive longevity if you don't abuse her during planning.
If you go to the 1.5's you will be able to use the existing propellers. You will also have the option of going to Labbed 30's once a baseline is achieved (to determine the correct recipe)and you will see a increase in cruise speed and top end.
If you stay with the 1.36:1 gears, 26 pitch props will improve acceleration, hamper cruise speed and fuel economy and maintain the same top speed or may even lose 1 mph.
Your current set up is doing what it is capable of weighing the actual HP you truly have and the fact that the slip % is 10.56% pulling stock 28's.

1.5: gear ratio at 5300 with BBLADES Labbed 30 B1's = 88 mph

Brett

Brett, did most Fountains come from the factory with 5 or 6 blade set ups? Would it help since I trim boat fairly high on top end with over all performance?

Well of course it depends on the model.
For many years Fountain Sport boats came with Merc Bravo 1 four blade props (mid 1990's).
Then there was a time frame Reggie wanted all the Lightning's etc. to have Labbed Bravo 1's. He asked us at Mercury Racing if we would cut him a deal. Dennis and I wanted to but the bean counters didn't think we should. So, Reggie started to use Hydromotive Q4's out of anger.

Since the early 2000's, the 5 and now 6 blade technology has come along. With the X dimentions getting crazy high, 5 and 6 blades have almost become mandatory. I still feel a less agressive X dimention with 4 blade props is a better option in some instances.

To answer your question, currently Maximus 5 blade props or Hering 6 blade props come on most all applications.

At BBLADES we have done many changes from 4 blade to our Labbed Maximus 5 blade conversions with extrordinary results. In fact, Fountain is sending their customers to us for this conversion.

You will gain wonderful cruise speeds (+4-8mph with our work) but the top end numbers may drop by 1-3mph with your personal low slip numbers. We can also make your handling incredible.
Most setups we do gain across the board.

Let me know if we can help.

Brett

Brett