4 Blade switch to 5 Blade ? Your experience
#1
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Join Date: Aug 2001
Location: Sacramento, CA
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4 Blade switch to 5 Blade ? Your experience
I'm hearing good things from two guys who switched from Bravo1 4 blade to 5 Blade.
Better hole shot & improved stability.
One person with twins went faster, the other single engine application did not lose top speed.
Both guys were 500 + inch supercharged.
I'm running HP500, Progharged at 9psi, 5500 rpm 26p bravo1 prop, IMCO 2" shortie.
If you've switched 4 blade to 5 blade or know of someone who has.......I'd be real interested to know your experience....before & after.
Thanks......
Better hole shot & improved stability.
One person with twins went faster, the other single engine application did not lose top speed.
Both guys were 500 + inch supercharged.
I'm running HP500, Progharged at 9psi, 5500 rpm 26p bravo1 prop, IMCO 2" shortie.
If you've switched 4 blade to 5 blade or know of someone who has.......I'd be real interested to know your experience....before & after.
Thanks......
#2
Re: 4 Blade switch to 5 Blade ? Your experience
Originally Posted by LFarr
I'm hearing good things from two guys who switched from Bravo1 4 blade to 5 Blade.
Better hole shot & improved stability.
One person with twins went faster, the other single engine application did not lose top speed.
Both guys were 500 + inch supercharged.
I'm running HP500, Progharged at 9psi, 5500 rpm 26p bravo1 prop, IMCO 2" shortie.
If you've switched 4 blade to 5 blade or know of someone who has.......I'd be real interested to know your experience....before & after.
Thanks......
Better hole shot & improved stability.
One person with twins went faster, the other single engine application did not lose top speed.
Both guys were 500 + inch supercharged.
I'm running HP500, Progharged at 9psi, 5500 rpm 26p bravo1 prop, IMCO 2" shortie.
If you've switched 4 blade to 5 blade or know of someone who has.......I'd be real interested to know your experience....before & after.
Thanks......
#3
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Re: 4 Blade switch to 5 Blade ? Your experience
I went from 4 to 5 and picked up 6 mph at cruise. Due to engine problems I have not had the chance to run WOT. Single 30' superboat
#4
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Re: 4 Blade switch to 5 Blade ? Your experience
Originally Posted by Pure Energy
I went from 4 to 5 and picked up 6 mph at cruise. Due to engine problems I have not had the chance to run WOT. Single 30' superboat
Would like to know your X dimension?
4 Blade prop make and pitch?
5 Blade prop make and pitch?
What power are you running in the Superboat?
I tried a 25P P-5X and had good take off/holeshot. Cruise was slower by 1 mph, than my 26P Bravo. Top speed was also slower with P-5X.
It seems that most people have good results going to a 5 blade from a 4 blade prop. I seem to be the exception with my 1989 27' Activator. Also, propshaft is 5.25" below keel.
Have to try one (or two) to find out.
#5
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Re: 4 Blade switch to 5 Blade ? Your experience
X dim is 1.5" higher than factory. Sorry that doesn't help but that's all I know
4 blade was a 26
5 blade is a 25
Hp was probably high 5s, but has just been rebuilt and dynoed 610 hp and 635 torque
Boat will be done this week so I will give better details next Monday. Shoot me a PM and remind me.
Also you might want to PM Titan. I think he had a 27 Activator and he may have some tips for you.
4 blade was a 26
5 blade is a 25
Hp was probably high 5s, but has just been rebuilt and dynoed 610 hp and 635 torque
Boat will be done this week so I will give better details next Monday. Shoot me a PM and remind me.
Also you might want to PM Titan. I think he had a 27 Activator and he may have some tips for you.
#7
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Re: 4 Blade switch to 5 Blade ? Your experience
From my experience you need big HP and a higher X-dim to make a 5 blade work better than a 4 blade.
I went from a bravo to a maximus and added a 2" shorty. I'm running 1300HP in a 26' checkmate and I like everything about this 5 blade. Hole shot is good the cruise is better and I gained 2mph WOT. My prop shaft is now only 3 1/2" below the hull.
BTW Blades labbed it to get these results.
I would give it a try, based on your info. Good Luck!
I went from a bravo to a maximus and added a 2" shorty. I'm running 1300HP in a 26' checkmate and I like everything about this 5 blade. Hole shot is good the cruise is better and I gained 2mph WOT. My prop shaft is now only 3 1/2" below the hull.
BTW Blades labbed it to get these results.
I would give it a try, based on your info. Good Luck!
#9
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Re: 4 Blade switch to 5 Blade ? Your experience
It's a 26" Mercury Maximus. 1.3 ratio at 6200rpm I was running 103mph with the 2" shorty Bmax drive. Works out to be about 12% slip. With a standard length drive I was at 9% slip, but it was 3 mph slower.
I've since increased boost and labbed the prop again for more rpm. The new top speed is still under wrap. I still have a smart azz by me that needs to go down.
In a week or two, I can give you all the new numbers.
I've since increased boost and labbed the prop again for more rpm. The new top speed is still under wrap. I still have a smart azz by me that needs to go down.
In a week or two, I can give you all the new numbers.