What size prop should I use

[Striper Blues]

on a 1989 25' grady white sailfish with a 460 ford King Cobra stern drive?<br /><br />I'm told 15x17, is that 15"diameter and 17" pitch?<br /><br />someone suggested going to a 15x15 how would that change performance?<br /><br />thanks,<br />Pat

 

[Bob_VT]

Re: What size prop should I use

Yes 15" diameter and 17" pitch... Your boat weighs close to 6000 lbs and according to the prop charts 15 X 15 would work but you need to match your prop with your outdrive type and be capable of achieving WOT with the prop. The 15 x 17 might provide more top end or be perfect.<br /><br />What is on the boat now?<br /><br />Bob

 

[Striper Blues]

Re: What size prop should I use

Bob, I'm told its 15x19, but I'm not sure how to measure pitch, I'll take a closer look in the daylight to see if its marked anywhere.<br /><br />So then its 15x17 that I'm shooting for...I'm trying to set it up like it was originally, afterall I have a new (not remanufactured) 460 long block that was just installed....<br /><br />thanks,<br />Pat

 

[Bob_VT]

Re: What size prop should I use

If you pull the prop off there should be numbers cast in the hub. Usually the pitch will be stamped in if not you can post the numbers and someone here will decipher it.<br /><br />Bob

 

[Boatist]

Re: What size prop should I use

You do not guess on the right prop. Too high a pitch or too low a pitch can destroy your engine. The right prop is the one that lets your engine turn the manufactures reccomended RPMS at WOT. To even start to find the right prop you must know you engines WOT RPMS.