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......

Re: 4 Blade switch to 5 Blade ? Your experience
 

I saw a 38' Scarab...with a 5 blade gain some efficiency at cruise speeds and get on plane with a bit less strain on the engines. They went from a Mirage 3blade to a 5 blade...it was probably worth the money. The were not happy as top end was the same...they need more power.

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

Re: 4 Blade switch to 5 Blade ? Your experience
 

Pure Energy,
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.

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.

Re: 4 Blade switch to 5 Blade ? Your experience
 

Thanks for the feedback!

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!

Re: 4 Blade switch to 5 Blade ? Your experience
 

ZT260,
What 5 blade are you running?
What numbers are you seeing, as in RPM and speed?
Russ

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.

Re: 4 Blade switch to 5 Blade ? Your experience
 

hmmmmm i wonder who that smart azz is :eek: ?

Re: 4 Blade switch to 5 Blade ? Your experience
 

I went from 4 blades to 5 blades and like what i got.better cruise speed with 6mph at the same rpms 3200.planing was better and i didn't wash out the props.top speed was about the same.just watch hammering it to get on plane the XZ drive on a 10,000lb. boat will not hold up.learned the hard way.

Re: 4 Blade switch to 5 Blade ? Your experience
 

Better hole shot
More transom lift
Better mid range

Higher probability of drive damage.

Overall it really depends on your entire package as to the results.

Big HP and Big 5 blades create difficulty issues in handling around the docks.