What prop should I buy?

[fredipuppy]

What prop do you reccomend for Grady White Seafarer 227 OMC 170 hp 1.77 final ratio. Boat is 22ft, deep V, cuddy cabin, I/O, 18 inch hull draft plus 16 inch outdrive draft, with people, fuel and cold beverages weight probably 4500 #, empty weight is apx 3700.

 

[Irv964]

Re: What prop should I buy?

What prop do you reccomend for Grady White Seafarer 227 OMC 170 hp 1.77 final ratio. Boat is 22ft, deep V, cuddy cabin, I/O, 18 inch hull draft plus 16 inch outdrive draft, with people, fuel and cold beverages weight probably 4500 #, empty weight is apx 3700.

Read this http://forums.iboats.com/showthread.php?t=287818 and tell us what your trying to acheive?

 

[fredipuppy]

Re: What prop should I buy?

I'd like to know what would a dealer put on this boat. I had a 15 1/2 x 15 replaced it with spare 15 x 17, both are damaged. Boat has not been in water, so best I can recall is max rpm i could attain is between 3200 and 3500 with these props. Best mph I could attain was between 28 and 32. That's probably my issue, mph, would like to get offshore faster. Factory WOT is 4200-4600. Engine runs great, maybe I could rig a little more throttle pull but I dont want to run this engine a constant wot 4000 plus.

 

[hwsiii]

Re: What prop should I buy?

Fredi, I show you need a higher pitch prop than what you are running if you have a 1.77:1 gear ratio. I also ran some numbers on prop slip and I show you have NO prop slip, and that can't be right. You need to check your tach, in my opinion it is wrong, unless the props are that bad and the boat is really underpowered. You need to use another tach to check it against because if it is right something is wrong. Although you did say the props are damaged. And you need to borrow a GOOD 17" prop to see what RPM you get. I also ran numbers on what pitch prop would be required to reach 4,600 RPM if the 15" prop was getting only 3,500 RPM, you would have to change to an 11" pitch prop to attain 4,600 RPM.


Prop Slip

H

 

[fredipuppy]

Re: What prop should I buy?

Thanks Chief, I'll shoot for 17. Tell me, how are composite props? Piranha composite props say they will exchange blades if one is not happy the the pitch they purchased. Only incur shipping charges.

 

[junior1113]

Re: What prop should I buy?

i would say a 15" that is a heavy boat with little hp. hole shot would be better wuth a 15. i know those boats and they are heavy. usually they have 225-250 hp out boards and run 15" props. not going to get that thing any faster than 35 mph would also get another tach to rule out that problem