Cobalt 269 Condurre Prop Reccomendations
#1
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From: Hartsburg, Missouri
I'm running 21P Mercury Cleavers. Is there a better option for cruising speed and efficiency. Or is this good for the 24 degree deadrise hull. thanks.
#3
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From: Hartsburg, Missouri
just wondering as, this is my first twin engine and I'm kind of having a hell of a time getting the boat balanced while trying to free up the boat for good efficiency yet maintain a level ride without porpoising a bunch,, same problem at full throttle.. boat wants to porpoise terribly unless I have a good amount of tabs in the water especially with the drives trimmed out a bit to run the boat with less hull in the water. Anyway just thought if you had some insight I would be glad to hear it. thanks.
#4
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From: OPKS & LOTO
I concur with Westcoast. Get a set of Mirage (3-blade) 21P props and try them. The rounded ear props will hold much better in the water than the cleavers and "should" alleviate some of your porpoising. You might find you need a set of 19P depending on the WOT RPM's. Check your engine specs for the correct WOT RPM and try different props to get you in the proper range.
#5
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From: Hartsburg, Missouri
I will see if I can find a set and see what they do. Would any round ear prop work? That is a round ear that is same pitch, and designed for a sterndrive and heavy boat?
#6
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John, sweet looking 269!
I have an 86 with twin 350s and I am running Mirage 3-blade 21p. I love the way the boat handles with them. Also, swapped out one lower so I have counter-rotating props. No more prop-steer, one less thing to deal with.
Let's see those interior pics...
I have an 86 with twin 350s and I am running Mirage 3-blade 21p. I love the way the boat handles with them. Also, swapped out one lower so I have counter-rotating props. No more prop-steer, one less thing to deal with.
Let's see those interior pics...
#10
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From: Hartsburg, Missouri
My first test with the old solid hub Mirage propellers went really well. Granted due to my blown couplers etc. I changed alot of things with the engines all aluminum manifolds , heads, and intake. However I doubt that did nearly what the props did.
Boat could put put along at 22 to 2300 rpm and stay on plane which about 2500 rpm was as low as I could go before with out falling off and sinking down off plane.
Cruising at 2500 rpm with the trims up and drive out just a touch to free up the boat I was showing 32mph on the speedo (not GPS). No poropoising and really was easy to drive and keep the boat from getting out of hand with porpoising.
At 3,000 rpm the boat was pushing 40mph on the speedo. Still good manners. Didn't test much over that as I was allowing everything to set in with all the other changes to the engine. I did a quick blast at WOT and was able to see 4500 rpm rather quickly. So I will report back later with the details on top end. But driveability is so much better I really don't care. The boat does everything better with the change and I really like these props much better over the cleavers. I just wanted to post in case any other owners are considering a change.
Boat could put put along at 22 to 2300 rpm and stay on plane which about 2500 rpm was as low as I could go before with out falling off and sinking down off plane.
Cruising at 2500 rpm with the trims up and drive out just a touch to free up the boat I was showing 32mph on the speedo (not GPS). No poropoising and really was easy to drive and keep the boat from getting out of hand with porpoising.
At 3,000 rpm the boat was pushing 40mph on the speedo. Still good manners. Didn't test much over that as I was allowing everything to set in with all the other changes to the engine. I did a quick blast at WOT and was able to see 4500 rpm rather quickly. So I will report back later with the details on top end. But driveability is so much better I really don't care. The boat does everything better with the change and I really like these props much better over the cleavers. I just wanted to post in case any other owners are considering a change.


