stainless prop pitch

[snagged again]

i'am running a 1750 Fishhawk with a 115hp 4 stroke suzuki with a aluminum prop
23 pitch i'am turning 4000 rpm at mid 40mph i want to go to a stainless prop and need to know if pitch should stay the same. the motor rpm range is 4000 to 5000 rpm. i want good holeshot but dont want to lose any top end...thanks again in advance

[Tiny_guy_sd]

You need to drop from a 23 to a 21....Or a 20 if they make it would be better yet.

[BlackSilver]

I think you'd improve both your hole shot and your top speed by dropping down to a 21-pitch prop. Your motor is lugging if you can only get 4K RPM at WOT.

Walk softly and carry a big fish.

Hans/MN

[Box]

I don't have a 115, but a 150. To me, it would seem that a 115 could not turn even a 21 properly... If I were you I'd go to a dealer who lets you try props and take out a 18,19,20,21 and see what works the best. I have heard (not experienced) that 4 strokes in mid range do much better with severely lowered pitch props.

Again, I have no real life experience expcet talking to guys at boats show regarding 4 strokes, or reading mags. But I doubt your 115 4 stroke can turn a 21"...

Good luck,
-Box

[fisherman]

I have the same boat,but a 115 Yamaha 4-stroke and T-8 kicker hanging on the back.

We fooled around with 19 and 21 pitch aluminum props; them put on a 19 pitch ss. 5100 rpm., slow hole shot and a porpoising problem.

Went to a 17 pitch prop--great hole shot, 5900 rpm. and no porpoising. Was running around 45 or 46 mph. with 500 pounds of passengers and storage compartment full. Probably a half tank of gas.

Motor is all the way down-top hole- and the prop was S.S.

[Hookmaster]

What brand of SS prop are you using?

[RK]

Hiya,
I have the same motor, and the same prop, on a 1760 Tuffy. Sounds like you need to get your RPMs up if you are getting to only 5k at WOT. You should be getting up close to the 6000 rpm mark WOT and trimmed all the way up. Rev limiter on the motor is 6300 (maybe 6250? - I forget). Don't want to hit the rev limiter of course, but if you are 1k rpms short at WOT, you are lugging a little.

On my boat, at WOT I'm at around 6000 rpms. I have a stainless on the way, and I'm dropping a pitch to a 22. Will let you know what happens (will be in this week sometime).

Your hole shot should improve with the stainless too, even dropping a pitch or two.

Box - For most 115s, you'd be exactly right. Suzukis have a gear reducer below the power head, so the lower unit ratio is 2.59:1. So they turn a pretty aggressive prop for a 115. Sounds goofy though - when my dealer told me he was starting me out with a 23 pitch, I thought he was off his rocker. Great hole shot on the things as a result though.

Cheers,
RK

[fisherman]

Hookmaster, will have to get back to you with that info. Will be heading out fishin early. My friend Nicols is on big eyes and I will not be home till Sat. eve.

Will try and remember to post a reply for you.