Prop - Am I on the right track?

[Unkle Ed]

Hey guys, I have an 03 Johnson DF70 on the back of a 03 Mustang 1600. Currently I'm getting 5200rpm WOT with a light load (2 people, half a tank of fuel and not much else) and it's even less when I'm decked out for fishing, holeshot could also be better. I've checked the motor height and it's spot on according to the thread on the verado owners forum everyone references too.

Currently it's got a standard ally 14x17 prop so I'm thinking I gotta go maybe down 2" in pitch to get it closer to the maximum 5800rpm.
So far I've found the following props that may suit:
BRP Viper 13 7/8 x 15
BRP SSP 13 1/2 x 15
Solas Stella 13 1/2 x 15

Can't really find anything else that is close to those with a 13 spline hub. So far I'm leaning towards the Viper simply cos it's the closest to the size I'm looking for. I'm also not sure what effect, if any, going down to 13 1/2" diameter will do combined with the lower pitch.

So what's everyones thoughts? Anyone know of any other props that may fit?

[FNQCairns]

Nah they will all be rubbish on your boat, just varying degrees of it.

Dropping pitch with that same or near equivalent diameter will make the boat a dog and even bigger dog than it is now but it will increase your WOT and give you better hole shot etc, worthy enough or closer if you wanted a ski prop although not fast obviously.

You need to drop diameter first, with luck if you can find a prop somewhere, any prop any brand any shape that is 3 blades but 13x15 and it will be worthy of a test.

next choice is do the same again but with a 14p, if the 15 doesn't pull quite enough rpm, get some cup taken out to reduce turning resistance do the opposite if it has too little turning resistance...same goes for the 14.

There is a massive hole in the dumb (off the shelf) prop market with virtually no option for props with less surface area and less cup, not everyone's rig nails these "utility" props in surface area and cup so mostly they give up and lug or overrev for speed all the time everywhere.

There are ways around this if one is handy and doesn't mind slumming with aluminum props for a while but none specifically of the shelf that I know of, there has been a flood of cheap aluminum props in the last few years, what chance a 13x15 or a 13.25x14 or a 12.7/8x15 you get the drift some of those will take the mercury torque flow (sp) hub...at least this widens the search over a few more brands but I forget these days what you might find at or close to those sizes above.

With luck you might just find yourself a 13x15 that fits and works of the shelf, you can sometimes get wrong engine brand props re-hubed to suit other engines so that's an option too.

[Lancair]

Hey Ed, where abouts are you ? I have a BRP 13 7/8 x 15 you can maybe try out.

[FNQCairns]

Oh crap, what a waste of typing, i just reread and your currently using a 14x17 not a 14x15 which i read it as, so ignore most of my post i really should have been in bed, hope one of those 3 gets you close.

One thought if it where me I would be interested to see how a 13 1/8x16 SS mercury prop would test on your boat.

[Unkle Ed]

Hey Ed, where abouts are you ? I have a BRP 13 7/8 x 15 you can maybe try out.

I'm in Brisbane but won't be home for another week, I'll probably end up ordering something before then but thanks for the offer.

Oh crap, what a waste of typing, i just reread and your currently using a 14x17 not a 14x15 which i read it as, so ignore most of my post i really should have been in bed, hope one of those 3 gets you close.

One thought if it where me I would be interested to see how a 13 1/8x16 SS mercury prop would test on your boat.

Don't know where you got the 14x15 from but thanks anyway for your indepth reply I was originally thinking of getting a mercury prop because everyone talks about them but found it hard to figure out how to get one with the right spline etc, the mercury prop guide didn't load any props up when I selected my motor and I couldn't find any other info anywhere easily so I gave up on them.

After doing a bit more reading it looks like the SSP might be the prop to go for due to it's design, but the Solar prop is certainly alot cheaper and I haven't heard anything bad about them so far.