Prop size of to speed

My 19' boat with a 220 hp

My 19' boat with a 220 hp 5.0 L currently runs 59 mph on a 14.25 x 23 3 blade stainless @ 4725 rpm 1 person 1/2 tank of fuel. What prop could I use to increase top end !

59 mph for a 19 ft 220 hp is v

59 mph for a 19 ft 220 hp is very good.

Do you have $600 - $1000 to spend on a custom made prop? That is the only way to get more!
How much? maybe 3 - 5 mph or a small bit more.

Put a 383 stroker motor that has ~ 400 hp and that should take you to 65 - 70 mph maybe a bit more. The real problem you will expirence is the limitations of the boat hull design. As you get more mph the boat will loose controll and start to fish tail NOT GOOD!

I would say you are near your limits with that boat.

If you really want to go fast put in a 502 HO and a bravo 1 and raise the X demension 1 Inch and I bet you could get 80mph plus!!

The hull is a Baja 1998 192 Is

The hull is a Baja 1998 192 Islander

That is damned fantastic for a

That is damned fantastic for a 220 hp 5L.
What is the weight of the boat?

Rod

drop to a 22P to get close to

drop to a 22P to get close to 5K RPMs

ROD S. I agree that is a very

ROD S. I agree that is a very good speed for a "stock" 220hp 19 ft boat!

There are several high performance propeller manufactures who can make one for your boat. Stainless Steel of course. One of my friends put a HILL performance prop on his 21 ft Checkmate stock 350 cubic inch mercruiser Alpha 1 1989 and he was able to get 63 ish mph clock with a GPS. The prop is what got him over the 60 mph barrier. $650 used!

Speed and power in boating costs big money for small amounts of gain!!

"Kg;
Know what you mean.
Las

"Kg;
Know what you mean.
Last year I replaced the stock 180 hp 4.3 in my 1996 20 ft Mirage with a Merc 320 hp 6.2 MAG MPI. I run a 21" Highfive on a 1.47 ratio Alpha Gen II.

Great swap and completely woke the boat up. WOT went from about 47 mph to just over 60 mph, but the hole shot and pulling is where you really notice the extra hp. Plus it just sounds a whole lot better, since I installed hardin side exhaust outlets. Only trouble is my neighbours don't seem to like me much anymore!

I have noticed that the hull gets a little squirrelly at top end. Plus the only time you can really let her rip is when the water is fairly calm, and how often does that happen?

I have not noticed any higher fuel consumption overall, since we do a mix of towing and cruising. The EFI is a huge improvement over the carb.

That's why I thought 59 mph with 220 hp 5L sounds too good to be true, unless the boat only weighs 1800 lbs or so.

Rod"