What is a good slip %
 

I have a 1992 Baja 24 outlaw and I am curious on what a good slip percentage would be? On my 240 sport same hull I ran a 23p mirage, with a bravo 1 at 4800 GPS just touched 65mph. That came up at 7% slip. Seems low to me.

That is a lower than normal slip number. Most hulls similar to yours are dialed in between 10-13%.
Tachs. are notoriously inaccurate and gps reading cam be slightly off which can adjust the number quickly.

Brett

Thanks for the info

was playing around with your prop slip calculator, and was a good tool for a starting point on what pitch to start with. I am going to start with a Bravo 1 24p as a buddy has one I can borrow for testing, if that is to small going to try a 25p hydromotive.

Best my 25 ever did was 64.7 at ~5050 = 11.7

What power plant did you have? What prop were you running ? I want to go to a 4 blade but don't want to lose too much top speed, however I hear great things about cruise speed, and handling also handling in the rough, and I am thinking a 25p hydromotive will get me 73ish. Have 502 EFI with right around 530hp as a power plant with a bravo 1 drive. Looking to prop to spin 5200-5400. If I do the calculations with a 10-13% slip that puts me at a 24-25p prop. We will see how it works out I guess

Slip numbers are a great yard stick for checking set up. In my experience, any time you can get to or bellow 10%, you're doing pretty damn good.
I had my old 24' Sonic at 8% and I can't get this one anywhere close even though they're virtually identical rigs.

I'm with BBlades and now doubting my #'s from the first boat.

so if i have 14.2% slip on a 96 22 scarab then something is not right?

No that isn't necessarily true. 10-15 percent is in the unwritten acceptable stage for your boat. However, increasing or decreasing slip numbers can affect mid range cruise numbers and/or top speed. We would need to discuss your application on the phone to get deeply into your options.

Brett

I am quite confident you'll be happier with the Bravo 1 versus the Hydromotive.

Brett

454 mag MP I (385hp) 23m+ in 50 degree and 2ftrs. Normal was 63 with LT load, full fuel and summer.
Load affected cruise by 1-2mph with 3 blade and was really slow to plane with 5 ppl but still didn't need tabs but even wife asked why it took so long.... Ended up with worked 22p b1 up pitched to 23. Lost maybe 1mph but cruise, trim, handling, time to plane with load all improved with bravo one and it wasn't labbed.
I would also start with 24p b1 since your trying to get rpms up. Check tach b/c 65 at 4800 is pretty low.

The question that I have is for the Mercury slip calculator- are these numbers the same for a Bravo III Drive?
Because if they are I'm less than 5% which from what I understand is pretty good.


3pointstar

-1 % is great.........17,1/2 x 26 merc lab five blade clever #6 ,dry sump 6 drive with 132 gears @6000 ,115 mph.......I think I punched it in right lol makes no sense

My thing is I don't want to lab my prop, not just the fact of spending $1000 on prop, but don't like that they get damaged so easy. Now I know I can get a 25p Hydromotive from hydromotice for $499, and then have the diameter cut down from 15 1/2" to 14 3/4" for $150. Guy at hydromotive says they have tested this set up on the outlaw and it is faster then the mirage +'s across the board. I have also been hearing some negative things with the B1's on my size outlaw. I am not against getting the B1 if it performs well, but I don't want to lab it, so the problem is I think the 24p may be too small, but I am pretty confident that the 26p is going to be too big. Regardless my goal is to hit 73mph or more which i think should be able to be done, but more importantly have a strong cruise speed 50mph+, and improve the attitude the boat has in the water.

What kind of comparing testing have you guys done with the 24 outlaws and what did you find out?

I'll chime in because my boat last season was identical to your setup with the exception that I ran a -2 imco on my boat. I had a hot cammed hp500 that put down 535hp. Here are my results to the letter

A stock bravo 24p 4 blade ran 70-70.5 all day every day at 5250 with an1 time exception it blipped 72...

I had a purchased a labbed bravo 4 blade 24 stamped BB2771 it would turn 5400 and bump the limiter when I would trim It up pretty good. When totally aired out it would run 73 every day and still run 71 with a full tank of fuel and 4 adults on board... I saw 75 which is like 8 percent slip which is amazing but that was on fumes, tail wind and absolute perfect conditions. It wasn't a real world every day 75.

Back to back runs with the labbed non labbed were as followed. The labbed prop had the attitude of the boat perfect. It had a slightly changed rake angle and cup added. It had awesome acceleration. Cruised at 50 at 4100ish I believe... It hooked up great and the boat handled perfectly.

With the stock 24 it honestly felt like we were dragging the anchor. It planed well and the boat rode okay but it seriously lacked the bite that the labbed prop had. It was even noticeable to my girlfriend. It required a ton more trim to loosen up and it chine walked slightly more.

I know that you say you don't want to spend 1000$ on a labbed prop, because of the money and damage. But dragging a stock prop through stuff is gonna damage that just as easily. I think Brett does a brand new prop for 825 including the prop and the lab work.

Lastly the prop I had was dialed in perfect from him. It unfortunately met it's demise at the Solomon's poker run I slung an ear off it and it was unrepairable. This prop had been labbed for 5 years... Other wise I would have sold it to you as I'm changing power this season.

You want the perfect setup and in my highly unprofessional opinion the only way to achieve this is to have a custom prop just for your boat. Be careful and don't run in the mud and it will last many years. Nothing cheap about performance boating and just be glad you don't have to buy 2...

We have done as many or more small outlaws than most anybody.
Don't get me wrong, I like Hydromotive propellers. We sell and service the. But, after hundreds if not thousands of Baja's over the last 21 years of doing this professionally, I can promise you a Bravo 1 carry's a Baja better than a Q4 Hydromotive out of the box..
You didn't mention working the propeller before. But now I know Thom or Todd has told you will need to cut the diameter down. They are right. The propeller will not work at 15.5" of diameter. It will drive the bow down. The Bravo 1 has geometry that dose less of that! And if you were to cut the diameter of the Bravo down slightly it would perform better too. If you were going to Lab it, it perform even better.
I now understand you are looking to do this as cheap as possible. Well, a cut down Bravo 1 isn't much more than the Hydro and you have the B1 geometry rather than the Hydro your trying to make work. I disagree with the cut down Hydro being faster across the board than the Mirage Plus. I disagree because we have tested these before too and the only way the 4 blade is fast at WOT is if the boat is set up wrong. (CG, X dimension etc.) The 4 blade may have better cruise but but that's just physics and you'll find that with most any 4 blade on sport hulls.

My suggestion is to try some other 4 blade propeller so you don't have to tweak any since you feel they will too expensive and the propeller will be compromised.
We have Revolution 4's (which I suggest for guys like you), and Fussion 4's, and OS1's as well as other we can put into our test program.

One more thing. There are all kinds of Labbing. We don't do you propeller like a race prop. It can be run through the sand or hit logs etc. without breaking. Plus they can be repaired like any other prop. If you hit a rock bar, it doen't matter what prop you have on, your going to damage it.

I'm just trying to offer some ideas for you.

Brett

Yes all very good points, and really what I don't like about labbing is the thinning of the blades, the cost is kinda whatever. I am not crazy about spending $1000 on a prop, but if it is going to give me the most ideal set up all around and not be thinned out so the blades bend, get thrown, our damage easy then I would consider it, Which you are saying that doesn't have to be done to achieve an ideal prop set up? How does it effect the prop when you take say a 26p and pitch it down to a 25p?

Wow great Info guys! Thread is full win! Keep it coming! I want to lower my slip %. Currently @ 11% with a 4-blade old Spinelli. 25p ran high 60's with 25 the. Switched to (borrowed) my brothers 23p Spinelli. Not designed for mine but made gains. Hit 70 right on the nose on a very very good day. Tail wind mild chop. Felt like flying and Chined up top. 25p rpm around 5600 and 23p rpm around 6500. Engine was designed for high RPM. FWIW. Deep V IMP. Going to send my 25 out soon and have it worked hit something coming into Joppa at idle with drive up. Looking for another 2-300rpm

You're looking to spin the motor 67-6900 rpm? What kinda hp and tq numbers and where are you going to make peak numbers if you don't mind me asking. I'm going to be spinning my new setup to 62-6300 and I get some grief from people occasionally saying that's really hard on things. It was built to run there all day every day so that's what I'm gonna try to do lol. How deep is the drive? My boat really woke up with a -2 imco. Propshaft height at 5.25 now. Works good. When it was at 7.25 it felt kinda sluggish, I have a stock 24 bravo that I could let you try out next season. Fwiw the spinelli props I've heard are fast but will spin similar rpms of equivalent 3 blade mirage style props. I.E a 23 mirage = 23 spinelli 4 blade. Don't know if this is fact but what I've gathered. Smaller diameter I believe?

Anyways if you want to try the new prop let me know.

Sorry I misread, you spin your current propeller to 5600 and want 2-300 more

Great info from BBlades.

If you're set up is close, your prop is the last thing to do. As one who knows from trying.........., a cheap prop ain't the same as a good prop. I have a bad habit of buying cheap used ones off e-bay too that may or may not be straight. I've written off a ton of them based on that that may have been crap examples to start with??

As another example of good Vs bad..... I have a friend running Cleavers on a twin O/B cat. He bought a set of (I think 15 x 34's) Ron Hills. He exchanged them w/him once or twice but still wasn't getting what he expected.
One issue was a 2 - 300 RPM variable between motors.
I was with him when he took them to a local, reputable prop shop. They put them on a digital pitch gauge and showed us a difference of TWO inches of pitch between blades!
I asked the prop guy if these props were coming from China and being re-labeld. He said yes.

Some times you get what you pay for.

I also have some experience w/labbing and agree w/Brent 100%.
I bought a set of e-bay Bravo 1's for my Sonic and was very disappointed in how they ran. Being cheap props means I'm willing to cut,grind, experiment w/them.
I made two mod's and drastically improved the charicteristics that I was after. That showed me they had promise.
My plan was to send them to Brent to be done right but have since put the boat up for sale.

In my experience, "labbing" is a general term. It is what ever you and your prop guy decide. Your guy should ask you if you're going through sand or is this your WFO only prop.

Bottom line? Back in my O/B racing days we had a prop guy that was called "The Prop God". There was a reason and he earned it!

you can also have your prop re-pitched without ''labbing'' it.

Yea I think I understand that thinning of the blades isn't necessary. So it looks like a 26p re pitched to a 25p with some cup added is a very possible scenario. Cupping adds bow lift correct? And from my understanding everything that would be done like re pitch, adding cup wouldn't thin the blades to make them fragile, so the durability of the prop should be the same as out of the box. Am I understanding this correctly.

I'll throw some slip numbers of mine out there. I run a 2011 checkmate ZT244 8.2mag 385hp with a bravo 1 X raised outdrive. Stock prop was a 26 pitch bravo 1, I spun it to 4600 rpm at 69mph 9% slip. I tried a 23 pitch rev 4 which I spun to 4900 rpm at 68mph, 4% slip. Then I tried a 26 pitch bravo 1 that had some lab work done to it. weather was cold and I was light on fuel. I was able to spin it to 4800rpm at 72mph, 9% slip. I'm getting a stage 2 PCM upgrade from whipple which adds 85hp. My question is will a 25 pitch rev 4 give me that low of slip number like the 23 pitch?

Quick question about slip

I have a Bravo III used the slip calculator and I'm less than 5%. Is there some correction factor because of the two props that I should consider?

please and thank you


3pointstar

Your slip is prob that low..... That duo set-up is very efficient . Just not good for top speed