Help?

I was looking to buy a prop for my motor but a couple of questions whAt is the pitch that comes on theese oem and what should i go with for a bit more speed. Right now it will do about 20 with 2 people and gear and about 25 with just me.

Here is a picture of the one thats on it

https://i52.photobucket.com/albums/g9/brandon__/8f13b419.jpg

Brandon, it would really really help if we knew what engine and horsepower you are talking about. Boat type and typical load would help also. Looks like an 18, early 20, or 25 Johnson to me but thats a guess at this point.

I thought i put that in there my bad its a 71 johnson 25 hp

Also what type boat do you have it on.Not much choices for that old of motor.I have a 1975 25hp Johnson & I have a 12 pitch prop on it but had problems with the brass shear pins breaking under alot of load.Your not too far off on speed though.I would leave it alone & just clean up the prop you have.

Its on a 15.6 foot flat bottom monark

Those older props weren't very efficient. Notice they're straight up and down, no rake to the rear like later model props are.

I'm not sure about the OMC 25's, but I do know about the older OMC 40's props. Chrysler props are more efficent props, designed with a rake and more blade in the water. A prop guru told me that he could hub a Chrysler prop with an OMC hub and get me more speed to fit my prop shaft. Tried it and gained 10 mph on the GPS. This was a 64' 40 hp Johnson.

He just happened to have bought a pallet loaded with Chrysler props, at an auction.