Prop riddle sunny vs formula
#11
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From: South Shore, Mass
Well.... been out a couple times, neither of which were ideal conditions. I did see 5200rpm,then over rev alarms, 67ish, too rough to start messing with trim and tabs and throttles. Both engines are running much better with tune ups and new emi exhaust with the short ss risers. With these Mirage plus 23 I still get on plane blow out and cornering.When cruising 35ish it's 3200rpm, I can move the steering about 90 degrees side to side and watch the tach rev as the outside prop breaks loose. Trimming is a no go. I'm gonna throw the 24p bravos back on and see what rpm I can get with those, now that the engines are up to it. Plus the cruise rpm was higher with the bravos too. On a side note new issue. Starboard engine runs great except once in a while between idle and 2500 rpm I get a alarm and engine stall at the same time. Sometimes it won't stall and recovers. Anything over 2500 and up it's fine. Checked wires cables, switches pulled yanked and wont do it on the hose. No codes. Just like loosing electricial power for a split second. Just in gear. ? When I do turn the key, off to on fast, I get the stall but no alarm. Maybe swap ecm and see if it travels. Twins gotta love them! :-)
Last edited by CC247; 05-27-2015 at 10:30 AM. Reason: edit
#12
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Check your ground cable on the back of the engine. I chased that one for months and it turned out that the cable was dirty. Needed taken off and cleaned, problem solved. Acted like someone was turning the key off.
I'm curious about 24p Bravos as well. Been blowing out my port engine when running hard. Just labbed my backup set of Mirage Plus 23s, hopefully that does it. If not, going back to trying others.
I'm curious about 24p Bravos as well. Been blowing out my port engine when running hard. Just labbed my backup set of Mirage Plus 23s, hopefully that does it. If not, going back to trying others.
#13
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From: South Shore, Mass
I had the Bravos on it last year and other than not being able to get more than 4K rpm both engines the props were much better out of the hole, cruise was faster They lifted the whole boat and I could trim them alot more. Everyone says my drives are too deep to use bravos but I like them. 24P should be just about right for me with stock power. You may need 26's with your power. I have a set of new 25P mirage plus. Took forever to get on plane and again couldn't get past 4K but that was due to needing a tune up. I'm setting the boat up for comfortable cruise and holeshot not top end. If I lose 2-3 mph with the Bravos so be it, I won't miss them. As long as I'm not lugging the engines I'm good. Fuel consumption was better with Bravos too, as if that matters.
#15
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Joined: Dec 2009
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From: Florence, Kentucky
Woa. That is NOT how you should be running across the water. Holly bow stuff, batman. That is a trip waiting to happen.
You are seriously trimmed to the moon. The "pad" is your running surface. Look at your angle of attack with the Bravos... The pad is not shaped that way. In reality, hydrodynamics I would think are playing against your favor. You're pushing water and not running on top of it. Makes even more sense why your props are breaking loose.
Sit the boat on trailer. Trim the drives until they are even with the pad. That's where you want to be. Maybe a "tap" of the trim above that.
Seriously, dude, do not run your boat like that. I'm not trying to say I know everything but the last thing I want to see is a fellow boater get hurt. Not to mention a Sunny owner.
I may not be Tres Martin but I have taken his course twice. I think it's something you should look into.
You are seriously trimmed to the moon. The "pad" is your running surface. Look at your angle of attack with the Bravos... The pad is not shaped that way. In reality, hydrodynamics I would think are playing against your favor. You're pushing water and not running on top of it. Makes even more sense why your props are breaking loose.
Sit the boat on trailer. Trim the drives until they are even with the pad. That's where you want to be. Maybe a "tap" of the trim above that.
Seriously, dude, do not run your boat like that. I'm not trying to say I know everything but the last thing I want to see is a fellow boater get hurt. Not to mention a Sunny owner.
I may not be Tres Martin but I have taken his course twice. I think it's something you should look into.
Last edited by Sunny32SSR; 05-28-2015 at 02:15 PM.
#16
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From: South Shore, Mass
The bravo picture may have been landing. I feel the boat more or rather better control with the bravos, straight ahead and corners. The pictures are just an example of how the props feel to me. Bravos up on top of water and Mirage Plus in the water. Relax- I know how to drive. Here-better?
https://www.youtube.com/watch?v=-E6ocgdr0IU
https://www.youtube.com/watch?v=-E6ocgdr0IU
#18
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From: Long Island n.y.
+1 lab the 3 blades. Rule of thumb is about 200 rpm per inch pitch. But if they are labbed it's about 100 if thinned out. But you can also cup the tips and tweet the ends. Just find a good machine shop that works on props. Tell them what is going on and they will know what to do. And if you have twins maybe think about turning in. It looks like it's a bit ass heavy. Just my opinion .
Last edited by Drew555; 05-28-2015 at 09:18 PM.
#19
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From: Florence, Kentucky
No need to be defensive. You seem to think you know what you're talking about but you're asking for help.
Sticks with the threes and listen to ^^^. Also, you're not running a surfacing drive. They're supposed to be in the water.
Sticks with the threes and listen to ^^^. Also, you're not running a surfacing drive. They're supposed to be in the water.
#20
Brett at BBlades can work the Mirage props to reduce the blow out coming onto plane and tweak any RPM needs you have. Since top speed is not your concern I would not lab finish the props. Brett did wonders for a buddy running 25" Mirage props having problems similar to yours. Bravos will lift the stern where the Mirages will lift the bow.



