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View Full Version : What Prop???


NOTALENT
03-06-2007, 07:46 PM
I need to get a new prop for the parents boat. Its a 1994 Falcon Thunderbird 18.6 fter with a 4.3 Merc, Bravo 1. Just a runabout boat. Normally seeds about 40-50mph What size prop should I get? I have no clue what they have on there now.
Any help is appreciated,
Thanks
fkboatman
03-06-2007, 07:54 PM
14.1/4 by 19 came on it from the factory you can go to 21 pitch with probably no problem
NOTALENT
03-06-2007, 08:09 PM
14.1/4 by 19 came on it from the factory you can go to 21 pitch with probably no problem
How were you able to find out that was the factory prop???
Thanks for the info too...:)
bordsmnj
03-06-2007, 08:56 PM
they made 4.3 liters with bravo drive's?? just curious.
fkboatman
03-06-2007, 09:12 PM
i am in the boat bussiness and thats the most likely size it came with, and you can go to like michigan propellers and look up that info or call the manufacturer who builds the boat. and the guy who made the comment about the 4.3 and bravo, you can order it that was as a power package from merc. but dont know why because in the case of a small 18 ft boat with any small block set up or v-6 a alfa is the only way to go........performs so much better,does not rob so much power as a alfa does and lot less drag
DelawareDave
03-07-2007, 02:58 AM
The correct size prop would allow the engine to turn the maximum rated RPM's @ WOT. If the pitch is too high, the engine won't rev to the max, if too low, the engine will rev too high.
I would agree with fkboatman. 17 or 19 is most likely what it had original. 21 may work, but verify with the tach.
fkboatman
03-07-2007, 08:32 AM
I would still have to agree on myself on the 19 pitch from factory, So tell us who won when you find out/of course no punt on you dave,just say to say i was right:)
NOTALENT
03-08-2007, 06:27 AM
Thanks alot guys, heading to havasu tommorow. I will let you know on monday.:)
bocco
03-14-2007, 10:10 AM
If you going stainless I ran a 21" high five on a similar size runabout with 4.3 alpha for years and loved it. Pulled 200 lbs up on a single ski and ran 50mph.
I think there is a five blade for bravo also.
DMOORE
03-14-2007, 12:09 PM
If you going stainless I ran a 21" high five on a similar size runabout with 4.3 alpha for years and loved it. Pulled 200 lbs up on a single ski and ran 50mph.
I think there is a five blade for bravo also.
Thats actually a great idea. with the 4.3 and a bravo, one wouldn't have to worry about overstressing the drive. It would shoot out of the hole and give goo performance on top.
Darrell.