Which prop

[Stud man]

I bought a new boat (new to me) and would like to know which prop would be best for fuel consumpsion

it's a 1993 Searay 290 with a single 7.4 454 V8 and a Bravo 2 outdrive

the prop on the boat now is QA1952R

what options do I have? Is that the stock prop?

Thanks
S

 

[QC]

Re: Which prop

Stud man,

Prop selection is based on your particular boat's performance first, so we need your current data on how she performs now to be helpful. You should take a read of the stickies above ^^^^

I'm getting a 17 1/2 x 23 from your existing QA1952R

Bravo 2s are not going to give you much to select from. If you are in your WOT window (you'll understand that after the read) then I think Stainless is the only answer and if you picked up a 5% fuel benefit I'd be very happy.

 

[Silvertip]

Re: Which prop

The iBoats forum has a pretty nice "search" function. I used the terms "Which Prop", "What prop" and "prop selection" as search terms and all three produced 217, 218, and 219 responses most of which would have answered your question. As QC pointed out, and the stickies at the top of the forum indicate, you cannot just slap on a different prop and magically make a boat an economy champ -- because no matter what you do, they suck suck fuel. The best prop is the one that allows the engine to run at or very near the upper end of the engine manufacturers recommended rpm band at wide open throttle with what you consider an average load. Yes -- we understand you don't run wide open all the time. But if the prop is wrong at WOT it is wrong at all other throttle settings as well. You need to determine what your current WOT rpm and speed is with the load you carry most often. "About" xx mph at "about" xxxx rpm with a xx/yyP prop is not an answer that can result in reasonable recommendations.

 

[TilliamWe]

Re: Which prop

...

I'm getting a 17 1/2 x 23 from your existing...

And I find it VERY hard to believe that that particular pitch would work well for your boat. First off, Bravo 2 props can be up to 21 inches in diamter, and you are going to want that with your "big ole boat". And secondly, even if you have a 2.2 ratio drive, I highly doubt that it will turn a 23 pitch to the proper WOT RPM. My dad had twin 5.0 V8s with B2s on a 30' Chaparral, and he needed 19 pitch props to hit a good WOT RPM.

Be prepared, Bravo 2 props are not cheap/