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Anyone running a four blade on their Evo x with a Suzuki 90? What pitch?
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Post I made in Eastcape Owners group Facebook page

It has been sometime since I have updated the group about the Evo X/Suzuki 90 performance. I had sent off the Laser II prop for cupping and that prop shop overcupped the prop resulting in terrible performance from the stock prop #'s. I finally got around to sending the prop off to a different shop in Brunswick, Ga to have the cup gauged to see where it was at and then adjust. The props cup was reduced from a #8 gauge cup down to a #2 Cup gauge. Today was a window for me to be able to swap the prop out from the Powertech OSN3 21p to the Mercury Laser II 21p #2 cupped prop and I was absolutely blown away by the performance. Great holeshot although I will need to plug the vent holes as they're not needed and a hindrance to holeshot, but nonetheless the skiff gets on plane fast. Top end into wind/current after playing with tab and trim was 45.5mph, a 4.5mph gain over the OSN3 powertech. Top end wind aided cross current was 47.4mph and 4.4mph faster than I've ever seen with the powertech. Fuel burn was much better I can say at 35-37mph I'm burning 5.8gph or so. All numbers are real world, once off the water I fueled up and only was 5.2 gallons low. I had the trolling motor and casting platform on the boat with 2 rods sticking up. It took some time but I believe this is the best performance I can get out of the setup. Any questions please ask.

This doesn't answer your question about what pitch four blade to run but I'd have to ask why you would want one as I cant see any added benefit.
 

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What was your engine rpm? With a 21P prop at 6300 rpm to get the numbers you are getting, it would need to be at a 2% slip for 47.4 mph and just over 5% slip for 45.5 mph.
Whereas the OSN3 at 6300 rpm would be 9% and 15% slip.
 

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What was your engine rpm? With a 21P prop at 6300 rpm to get the numbers you are getting, it would need to be at a 2% slip for 47.4 mph and just over 5% slip for 45.5 mph.
Whereas the OSN3 at 6300 rpm would be 9% and 15% slip.
According to the picture of my GPS its 47.4mph @ 6250 and 45.5 @ 6062. You can go ahead and throw any of the prop slip calculations out the window as far as I'm concerned. When I dialed in the prop on my Lostmen and gave Ken at prop gods the numbers he was saying it was impossible as I had negative slip numbers. So either 3 different GPS units are wrong or the slip calculations are not exact math.
 

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More likely the prop is not the labeled pitch, math is correct, just the inputs are wrong. I am using a PowerTech PTR4 18 pitch and would like to get a 3 blade prop. Also would like it to be a little more stern lifting, rather than bow lifting. Lots of people like the Mercury props.
 

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More likely the prop is not the labeled pitch, math is correct, just the inputs are wrong. I am using a PowerTech PTR4 18 pitch and would like to get a 3 blade prop. Also would like it to be a little more stern lifting, rather than bow lifting. Lots of people like the Mercury props.
Prop was thrown on a 21 form block by my prop guy, it has also had cup added which the calculators dont factor in. Personally I don't use the calculators as they've never been close. Blade style is also a factor in which the calculator doesn't factor in.

What skiff are you running?
I was not a fan of the PTR3 I ran and preferred the worked OSN and obviously the Laser over it by far.
 

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BT Vengeance. What did you not like about the PTR3?

The BT is not a performance hull and the PTR4 seems to have bow lift, which is not all bad because if the bow is too low it steers like a drunk aircraft carrier. But a little more stern lift I think would help and reduce the use of the trim tabs.

Guess I need to call Marcus at PT, but keep hearing great things about the Mercury props and might have to look into one.
 
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