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Old 10-10-2020, 10:28 AM
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1992 Cobalt 243 Condurre 4100# dry weight w/ a ‘06 (crate) 502ho Bravo1 1.50 ratio...450ish hp. Running pretty damn good after 4years of solving PO issues. Lake elevation is 2128’.

Last weekend WOT= 56mph @ 4600 on a 3year old Bravo One 22p prop. Overall performance is great now but but would it be”greater” with a prop change to 23 or 24?

thanks!
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Old 10-10-2020, 01:18 PM
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You don't have enough WOT rpms as it is. You should be running 5000 rpms.
You may be able to gain some top end speed and switching to 23 Mirage Plus.
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Old 10-10-2020, 09:09 PM
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Check your tach accuracy first. 4600-5000rpm is suggested operating range. Assuming the tach is correct you might go a little faster with a notch less pitch of same prop model which will bring the rpm up. Might go faster with same pitch in a Mirage Plus. Dropping a blade will allow higher rpm which should equate to more speed. The boat will handle different with a 3 blade compared to a 4 blade. That's something you'll have to experiment with and see if a couple mph is worth the handling and fuel consumption difference of the two.
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Old 10-10-2020, 10:44 PM
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You need more rpm. More pitch won't do that. I would start with a 21" MIrage Plus. Your tach is likely fine.
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Old 10-10-2020, 11:17 PM
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Originally Posted by Trash View Post
You need more rpm. More pitch won't do that. I would start with a 21" MIrage Plus. Your tach is likely fine.
Oh crap yes, I was going in the wrong direction...21 does sound about right. Thanks for straightening me out guys.
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