Bass Cat Boats ?

[fishnfireman]

Curious as to what kind of prop slip numbers to expect from the Eyra I with a load.
Also wondering if youve done much testing on that boat with the new Merc V8.
Thanks Mike.

[BASStex1988]

If you ever make is south from Amarillo I’ll be happy to meet you at the lake. Just got in a 20 eyra with the 250 4stroke. Just shoot me a message if you would like bud.

[fishnfireman]

If you venture over to Amistad ? I leave my boat down there in the winter and normally go down on a regular basis however the fishing is tough with a capitol T.
Still working on getting my new rig setup.
Curious about slip numbers . I heard some crazy numbers from an Eyra owner and wondering about some others. So far none are forth comming.

[BASStex1988]

Did you get an eyra yourself? I will be getting some before long m. Just have to get my prop selection a little bigger. I will head to amistad every now and then

[fishnfireman]

No sir.. I just bought my 3rd Allison in 20 years figure this will be my last new boat.
Trying to gain info to know what to expect with V8's and the new LU. The reports so far are all over the place. Would like to hear from some more BCB owners to hopefully back up one report I saw.

[FastCat04]

I'd probably research a bit here, but I moved "Engine for an Eyra" topic started by others to help....

[fishnfireman]

I'd probably research a bit here, but I moved "Engine for an Eyra" topic started by others to help....

Thanks.... but I see nothing there to answer my question about slip numbers.

[FastCat04]

Probably because most aren't directly interested in slip %'s. Just rpm & top speed. Over the years very few have gotten into the calculations to derive slip #'s because it's not tangible. I know my slip #'s went down 1.82% when the only change was when I (215lbs) got out of the boat. That's a 37.52% reduction in slip ! Which is basically irrelevant to anything and anyone other than my boat, my prop, my jackplate, my trim setting, my weight balance. (Fury 3 24,25,26 with the typical 2.5% Fury cupping as Don Weed mentioned)

New L/U on the 4-stroke does have lower slip #'s than my Gen 2 TM L/U on my 2018 Opti. Even using the exact same prop...(same one, not just same model) the 4-stroke is slightly faster at same rpm. (and I have dual graphs, garmin box & dual poles on this Eyra that I didn't have on my 2018) !!!

[fishnfireman]

Top speed and RPM is all I need to check the slip numbers..Thats all I'm interesetd in !
I figure Mercury and some others are interested in slip numbers. If not, why spend so much money on R&D and use the better slip numbers in there marketing promotions for both props and LU's.
I also figure they would be just as interested as myself to learn how one can achieve 0 slip. So far I've not seen where they have been able to achieve that with any of there props. Not even there extra stiff labbed props from Mercury racing.

[Elwood]

I have an Eyra with a 250 SHO that is strong and post great numbers. 84.4 GPS with a 27 pitch T2 @ 6200 RPM......7% slip

[fishnfireman]

I have an Eyra with a 250 SHO that is strong and post great numbers. 84.4 GPS with a 27 pitch T2 @ 6200 RPM......7% slip

When is your new one set to be delivered.?

[Elwood]

I should have it before X-mas or just after the New Year. I am looking forward to a new learning and driving experiences. Planning on starting out with a 30 Bravo 1 Lab and will work things out from there, Was going to start with a 28 pitch but BCB has already hit the limiter very easily with that one. I do believe the the Max 5 will find its way to my house before it is all over. I'll post numbers and experiences as I go.

[fishnfireman]

I should have it before X-mas or just after the New Year. I am looking forward to a new learning and driving experiences. Planning on starting out with a 30 Bravo 1 Lab and will work things out from there, Was going to start with a 28 pitch but BCB has already hit the limiter very easily with that one. I do believe the the Max 5 will find its way to my house before it is all over. I'll post numbers and experiences as I go.

Now that will be a merry Christmas..
If you get a chance try a pro max, they seem to run stiffer than the bravo and do well with the new SM LU. I got hold of a used labbed 28 max 5...Its to small but the hole shot will peel your eye lids back and it pulls HARD way past 80.

[OldTimer57]

Not sure why you would care about BCB slip numbers if you have an XB hull. Totally different animals. BCBs generally run 2.5" or more below the pad. Allisons are on the other side of that running well above the pad. Different styles of props usually. A sporty gear case most of the time as well. BCBs generally are less than 10%, over 5%, so that's a reasonable guess for range. You will see someone claiming 0%, but it can't happen of course...

[Bass Cat Boats]

The company has done extensive research on that topic with the V8 and you will notice the Eyra in those early Mercury promotional videos. They tend to feel 8% is a good number. Most Prop calculators get you close enough though the factory uses their own formula.

Now if your talking about the new Sportmaster case then all bets are off at s that thing continues to change slippage dependent on length of the run. Toss in the CNC Clever and a Max5 with more variation and good luck. We have found best results on our product with a Bravo.

[fishnfireman]

Yes sir that sounds about right.
Saw a report where the numbers came out to 0% with a 250 XS and the new TM LU ----needless to say was somewhat skeptical.
Best I've heard from the SM LU is 5% with a Pro max. I have a Max 5 that hope to run next week on the 250R. Be interesting to compare my numbers with Elwood when we both get things ironed out.. I'm still in the testing mode trying to get things tournament ready.
Thanks.

[Elwood]

fishnfireman.....I am also very interested in your findings with the Max 5. While we have very different hulls I believe that it will be possible to compare notes and get our rigs tuned. As stated before I am starting off with a 30 Bravo 1 lab. I am also wanting to try some Hydramotive products as well as the Max 5. I do have a friend that is local that has several high performance prop that I can run. I am not expecting the Allison numbers you will see but do believe I can keep up with the Ballistic numbers being posted. I have a large learning curve to get through and safety is number one. Looking forward to running this boat and getting the optimum number out of it.....I am glad the you have a head start and can share info that I will need before I get started.

Side note for the slip numbers that are not adding up. Fury props are normally pitched a little stiffer than what is stamped on them. This might account for some of the slip numbers that do not add up. i do know that I have been called out for the numbers that I have posted and it was easily proven with video. For the most part it is just hard to lie about numbers with todays tech. I believe the numbers posted but would think that the prop is a little more than stamped.

[FastCat04]

Thanks Elwood ! This is my post that Mike can't understand. Note, there are no slip #'s ever mentioned because everyone knows Fury's have a steeper pitch. Since we don't have any factual data on what that # is (estimates are 25 Fury = 25.7")...then solving the equation for actual slip #'s is just a guess. But the facts are below:


OK guys....did more testing yesterday to help answer some questions about props, tuning and the new 4-stroke. What I found will also help answer some of the slip questions that keep coming up.

Baseline:
Same 2020 BassCat Eyra I mentioned in earlier replies. 250 ProXS 4-stroke. Ultrex 112, 4 AGM/wet cell batteries, dual front graphs up/mounted on bow, dual power poles, fully tournament loaded with everything including full cooler of drinks (no ice), all tools, spare prop, 20 gal fuel in R tank, 10 gal fuel in L tank. My son Will (160lbs) and myself (215lbs). Air temp 55 degrees. Altitude 223'

All tests were from standing start and top speed measured in 1.5miles of run room. (no 2,3 or 4 mile runs to squeak out the last few mph). All were done with 2 way validation in a still lake with no current.
Test run 1: Will & I in boat together. Stock 24p Fury 3. 78.5mph @6200rpm
Test run 2: I got out. Will solo. Stock 24p Fury 3. 80.0mph @6200rpm
Test run 3: Will solo. Worked (depitched) 26p Fury 3. 80.5mph @5900rpm
Test run 4: Will solo. Stock 25p Fury3. 80.6mph @5980rpm

So...what this tells me is several things.
1) if we had more room there was some left to be found with the 25 & 26
2) 6200 must be the limiter as we ran that max with the 24 regardless of direction & load
3) boat speed is almost 3 times more sensitive to weight than prop pitch or rpm (see difference between run 1 & 2)
4) stock props had a lot less bow lift than the Ronnie Gilbert worked 26p
5) we decided that when fishing with 2 people the 24 is good year round, but for us we will run 24 summer & 25 winter
6) holeshot was best with 24, then 25, then 26 (as expected)
7) if boat was empty/light and we were only looking for top end...the RG 26p probably had most potential as it required noticibly less trim angle
8) physics still apply. Aero drag alone increases at square of speed. Ie...it takes x4 times the hp to go x2 as fast. Plus add in hydrodynamic drag and it's more than that. For our particular aero package (graphs, ultrex, poles....plus our weight balance)..80-82 appears to be our 'wall'. I'm sure if we pulled the dual front graphs, the garmin control module (10lbs in nose), swapped the Ultrex for a slimmer unit, removed fuel, food, clothing, tool bag and didn't have every compartment stuffed with fishing gear that we could hit 85+. But for what? If we couldn't fish...then I'd just buy an Allison or HydroStream race boat. So for now...we'll just be respectably fast for a fully stocked and comfortable tournament fishing boat. And....we've never been passed...ever.... by anyone in anything in real world tournament conditions.

[Elwood]

Great write up and post Fastcat! I feel like you might even pull a few more mph out of your Cat with a larger diameter prop that is designed for 4 strokes. The fury came out just before the 4 stroke technology got popular and was designed for 2 strokes. 4S prop don’t vent and are normally ove 15 inches in diameter. I know the T2 (15 1/4 in diameter) ran very strong on my SHO and nothing else I tried could touch it. I have been told that I can not he a hub for the fat shaft pressed in to a T2. I will check a few other sources. I am just suggesting that you try a few other props than the Fury. I have ran much faster with others.

[fishnfireman]

Fury's not the only prop Merc makes that runs stiff, besides any worked prop with added cup can still be figured.
The original quote I questioned was "Installed box stock 24p Fury-3....runs 80 @6150 in mid 80 degree temps".

So lets use your estimate of what the adjusted pitch is and punch in the numbers.. Merc. and Bass Cat Boats say you can figure about 8% slip Elwood says 7.. I'll do you one better and give you 6% which is almost unheard of. Plus will call your 24p Fury a 24.7 ..
1.75 gears, 24.7 pitch prop @ 6150 rpm's with 6% slip = 78mph
Now lets do the same with your 25 pitch Fury........."Test run 4: Will solo. Stock 25p Fury3. 80.6mph @5980rpm"
1.75 gears, 25.7 pitch prop @ 5980 with 6% slip = 78mph

Those are some generous numbers but still 2mph+ short of your unwitnessed claims.According to your report.. You weren't in the boat for 3 of those runs ?? Never seen a fully loaded boat with power poles run over 80mph with those gears @ 6150rpm and a stock 24 pitch prop. Seeing is believing in my world. .
As for this comment... "And....we've never been passed...ever.... by anyone in anything in real world tournament conditions"

You need to get out more !

See if this helps There are variables that can be adjusted but the math is correct !
https://www.mercuryracing.com/prop-slip-calculator/