Please help with boat/propellor setup???

[Ranger115hp]

I have a 2004 285 pxl Stratos. My old prop s dinged up pretty bad, so i decided to get a Original Raker 14.5 x 24 off of the Boards. The problem is, i took the my old prop off same diameter and pitch(Model Unknown) and put on the new prop. With the beat up prop i was running about 58 MPH at 5100 RPM's. The new prop is is only getting about 5300 RPM but only a top speed of 51. I did notice that my old prop did not have any vent holes in it while the raker has three Vent holes.
Does the vent holes being open matter or not? and if so where can i get some for this prop?

Since i took of a 14.5 x 24 pitch prop off and replaced it with the same pitch, should i have to adjust my jackplate?

I am just confused on what to do? Any help would be greatly appreciated.

I also posted this in the props forum as well. I just figured the great guys on the stratos forum might be able to help out as well

Thanks
JUSTIN

[Buccaneer]

What was your old prop? What size motor and what are your measurements, prop shaft to pad? Do you have a jackplate?
I have a 2004 285 Pxl with 150 Johnson and 6" jackplate. Running a 24 Raker with prop shaft at 3 1/8" below pad I turn 5300-5400 rpm's at 62 mph GPS. I tried a 25 Tempest Plus but it would not out perform the Raker.