Bravo I prop
09-16-2005, 02:24 AM
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Bravo I prop
Hi! I just got new Bravo I 26P prop. Before I had Mirage Plus 25. With Mirage I had max speed 61 mph (4800 RPM, gear ratio 1,63). With Bravo RPM remaned the same, but max speed was 58 mph. I measured the pich of Bravo and found out that it varies from 22-23 (smallest at the centre of the blade). Is it normal, that real pich is so much smaller (should be 26)?
09-16-2005, 06:38 AM
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Re: Bravo I prop
Most of the Mercury props are not the pitch they are marked. The Bravo 1 props are lower than they are marked. As you go to the higher Bravo 1 pitches you will find the difference between the marked pitch and the actual pitch to be greater. It's not unusual for a 36 Bravo 1 to have a pitch of 33, out of the box.
The actual pitch of a stock 26 Bravo 1 should be about 24.5 - 25. Is your prop stock or lab finished?
Matt
The actual pitch of a stock 26 Bravo 1 should be about 24.5 - 25. Is your prop stock or lab finished?
Matt
09-16-2005, 01:05 PM
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Re: Bravo I prop
You have about 17% slip at the 4800 at 58 MPH with 1.63 gears. you really should be from 11%-14% slip.
Give us some specifics on your boat, engine and set-up. Maybe we can come up with some suggetions for you.
Julie
Give us some specifics on your boat, engine and set-up. Maybe we can come up with some suggetions for you.
Julie
09-18-2005, 02:15 AM
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Re: Bravo I prop
The boat is self-made 23' deep V (28 degrees). Weight is 3000 lbs. Engine is Crusader 350 (270-290 HP). Sterndrive is Volvo Penta 280 (with self-made propshaft to fit MerCruiser props). You can see some pics at www.navis.ee (section "sport"), there are some clickable pics.
10-06-2005, 11:05 AM
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Re: Bravo I prop
Correct me if I'm wrong...my Baja dealer advised me that when going from a Mirage + to a Bravo I, you're supposed to go down[U] by 1 pitch due to the extra blade or you will lose top end. So estonian should've gone to a 24P Bravo I. Was I incorrectly advised ?
10-06-2005, 04:14 PM
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Re: Bravo I prop
Rocko, you are correct! If you are running at the appropriate RPM then indeed you would need to decrease one inch of pitch to compensate for the drag of the additional blade.
Julie
Julie
10-09-2005, 10:32 AM
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Re: Bravo I prop
Here's a question for you...What is the approximate RPM gain when going from a 28P Bravo I to a 26P ? I have a 28P now and am only turning 4400-4500, do I need a 26P or 24P Bravo I to get to 5000 RPM ? THANK YOU, Rocko C. 
Originally Posted by throttleup
Rocko, you are correct! If you are running at the appropriate RPM then indeed you would need to decrease one inch of pitch to compensate for the drag of the additional blade.
Julie
Julie
