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MMW cavitation plate vs tunnel tabs

Husqy510

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We have an 03 26' Howard cat which we rigged for the 1st time last year. It has a N/A 540 which made about 720 on the dyno (probably mid 600s with accessories and exhaust). Currently we're spinning a 28 prop which works great once on plane, but with 4 adults it struggles to rollover. I was thinking about adding a cavitation plate to the outdrive or fixed tunnel tabs. I'm leaning towards the cavitation plate because I don't want to drill a bunch of holes in the transom. I'm looking for something that will help with coming on plane and decrease the load on the outdrive.

Any suggestions?
 

2FORCEFULL

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i've had great results with tunnel tabs... they handle ruff water better as well as get on plane better...they stop it from kite ing off wind rollers
 

$hot

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would be great to see some pics!
 

02HoWaRd26

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Simply put, there is zero downside to the MMW wing plate, and it’s 300$ and a couple small holes drilled into your drive. I’d definitely try that first.

However with your hp and boat, wonder if your X isn’t a little too high.
Stock lower or a shorty?
 

Husqy510

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Here's a pic of the transom. Pretty sure the outdrive is a stock Bravo
 

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Husqy510

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The boat drives great and has no porpoise. I'd actually like to try a 30pitch because the motor pulled 5600rpms easily and I'm sure I could trim it up a bit more, but I assume that would make it even harder to get on plane
 

ONE-A-DAY

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Try a max machine works wing plate, cheap, easy to install and makes a big difference before you go and spend more money and more headaches than you need to.
 

2FORCEFULL

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LOL... after looking at the transom, I have the fix,... but it'll just start the shit show of yard dogs barking....
 

2FORCEFULL

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the getting on plane problem is the big noches in the sponsons
 

THE Cat Sass

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I have some experience with the MMW cav plates on a 28’ Speedster. The worked exactly as advertised to help control the blowout prior to flop. That said if you don’t have the low end torque to blow out the prop the plates wouldnt be the answer. It was a game changer on the 28 for sure, I could essentially get a little momentum, set the sticks to 1/4 throttle and it would roll right over.
 

Husqy510

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Just ordered a polished cav plate from MMW which I hope to install on Friday. I'll update the post after we try it
 

Husqy510

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A friend with a lot of experience setting up performance boats mentioned the cavitation plate can add a lot of lift to the transom, drastically changing the handling. He also mentioned that the addition of the plate will require more positive trim at speed. He wasn't opposed to it, but mentioned those potential issues.

Did those who added the plate notice these characteristics?
 

wet hull

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My MMW made a world of difference. Boat rolls over great with full tanks and 2 people. 8 people and full tanks not so much. This is where it changed the game and made the rollover easier and faster. You will not he disappointed.
 

Husqy510

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Thanks, so far I haven't read anything negative, but want to make sure I'm informed.
 

02HoWaRd26

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A friend with a lot of experience setting up performance boats mentioned the cavitation plate can add a lot of lift to the transom, drastically changing the handling. He also mentioned that the addition of the plate will require more positive trim at speed. He wasn't opposed to it, but mentioned those potential issues.

Did those who added the plate notice these characteristics?
Yea idk about any of that. The only change i noticed was getting on plane, and that it helped with low speed turns (180°) it helped reduce the blow out of the prop.
 

Motor Boater

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What does the plate look like? I didn’t see it in their website. My 28 Bullett has issues rolling over when it’s loaded down.
 

2FORCEFULL

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Thanks, so far I haven't read anything negative, but want to make sure I'm informed.
I got in this same situation,,, the fix for me was I did a 2'' drive spacer... it made a world of difference, boat handled better all threw the throttle... but the neg. was it lost 2 mph on the top end.... for me it was a great trade because I wasn't after max speed as much as usability
 

2FORCEFULL

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A friend with a lot of experience setting up performance boats mentioned the cavitation plate can add a lot of lift to the transom, drastically changing the handling. He also mentioned that the addition of the plate will require more positive trim at speed. He wasn't opposed to it, but mentioned those potential issues.

Did those who added the plate notice these characteristics?
I agree with your friend... could get wierd at WOT pushing the COG forward....
 

2FORCEFULL

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On this boat,... the only person I personally would talk to is Gene...
 

02HoWaRd26

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What does the plate look like? I didn’t see it in their website. My 28 Bullett has issues rolling over when it’s loaded down.
I can go take a better pic if needed but i screenshot this from another to get you an idea.
665D6942-6A8B-41E0-9440-B301B488DA0A.png
 
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