Need Help What Prop?
 

I have a 1990 Powerquest(Powerplay) Spectra222 with a 270 HP Mercruiser Alpha One.Im not getting the Speed or RPM I think it should be getting.It will only turn up @ 3800 RPM and 30 Knots on GPS.I know I have the wrong prop on it and was wondering If anyone Knows what prop I should be running.Also any info on this boat would be great as I can not find anyone who has one or any info on the net about it. Thanks.

With the info you gave I'll guess that you should drop down 4 inches in pitch and see how that works. How is the boat getting on plane? I would think if you are only getting 3800 it must be real slow out of the hole. If it is good to plane you might have more than prop problems.

What prop are you turning? I am guessing by those numbers that thing must be huge!!

That is a lot of boat for a small block.
Most boats that size at least have a BBC.
Before you spend a lot of money trying to get it to go faster I would think twice about selling it and buying one with a BBC.
I went that route before.
You can easily get 400 HP out of that motor but then you will have to change to a BRAVO drive and in the long run you will have spent more money than you would if You bought a different boat.

I had a friend with the same boat with the 350 mad and if I recall he was running a 21p mirage, His ran low 50's. Not to bad with a small block. As far as details I have a 93 brochure and it states the following, Center line 22'2", Beam 8', Hull 22 1/2 degree deadrise, fuel tank 50 gal, weight 3,500lbs with a small block. What size prop are you running?? If it is a 21 you may have a spun hub??

Its terrible out of the hole,very hard to get on plane.Ive tried a couple of props that I had lying around so its not a spun hub.I will look at the props tommorow and get the pitch and diameter,I did put on a hyrofoil doel fin type thing that seemed to help get on plane a bit but took about 3 MPH of the speed.The motor is in good shape was well maintained and has about 290 hrs. on it since new.Boat is put away for winter so I cant try anything till spring.