Fasterboatman

Hello all,

An 8 month project plan took over two years. As with most boat projects,it always cost more, takes longer, and never quite meets the goal. Covid, and issues with a "bubba" rigger had prevented me from getting this project finished per the plan but I am getting really close now to being back on the water ad having fun. The 572 engines from Skip White have been flawless so far. Huge thanks to Skip for his consult on cam and compression choices. The XZ drives seems up to the task, but props are my current issues. Bblades is being very helpful with their testing program. Anyone who is looking at props should go to their site. Brett is very helpful and their staff is the same. bblades.com

I have a bunch of pictures of the build up and installation, but I will need to work on getting these into albums. I will tell you that Greg Ray of Plano Marine has been very helpful in making sure I am getting back on the water. I wish I could have found a professional rigger that is in the North Texas area, but I ended up paying a lot for work that never got done. With many helpful friends, (thank you Chris, Bob, Greg and John!), and of course many of you on this forum that helped, it is now nearly done. Thanks to all! Oh, yeah, and of course the CFO (Thanks babe!). Also kudos to Jeff Stull at Hardin marine! Always has a great feedback and helps however he can.

I have about 30 hours of testing and engine break in, and thus far, except for not yet making plane, everything is going pretty well. A few glitches with the power-steering, and some every hard to trace electrical issues, but otherwise im happy to report progress is been excellent. Of course, with these engines, and such a big heavy boat, Im sure everyone would like to know how fast etc. I will keep you all posted.

The Edlebrock Pro4 fuel injection is awesome! It is proving to make this whole process be just a smart pad away. Very cool.


So far I cant get enough prop bite:
Mirage 21" 4b, and blow out before plane out at 3k rpm
Rev 4 25" blow out at 2500-2700 rpm.
Next test is a Maximus 5 24"

I suspect that a 6 blade may be in my future, but hopefully the 5 blade will provide some good data and get it on plane. Ill keep you all posted!

Finally on the water in Texas,
-j

mcollinstn

Big heavy boat.
Big torquey motors.
Wimpy Bravo drives..
I do not trust them with more than 500 ft lbs of torque.

I've blown up my share of Bravos. I've watched friends throw upgrade after upgrade into Bravos and still blow them up. I've watched a friend upgrade to a BMax and then twist the vertical shaft in half.

The weight of your boat is the killer..
A 900hp motor thru a Bravo on a light boat is pushing it..
But a heavy boat with 600 ft lbs thru a Bravo is a grenade with the pin already pulled.

Best wishes and I hope your Bravos magically last forever.

Sonic30ss

I’m happy for you that you’ve gotten the boat in the water.
I want to share my experiences and another’s experiences (47excalibur) on the site with the Excal.
I put 540s making 640hp/700tq in my boat Matt had something like 1200 hp blower motors. We both had 2:1 B3 X drives, in my case I was pushing the vertical shaft through the top of the older X drives, when I switched to the new versions with the rib cap it would twist the shaft in two, if the shaft survived 10-12 hrs it would eat the gears. I also had cavitation burns on the props so bad pieces were missing. Brett did an awesome job getting the props to bite and not burn, however the drives would disintegrate faster.
The bravo drive just cannot handle the torque and weight of this combo.
We both went to Arnesons, Matt’s boat is still running on a big lake (LOTO?) I just dropped mine in the water yesterday and I’m working on a few new boat items, I should have it sorted by the weekend to take some test runs.

Im not trying to discourage you, merely trying to let you know what you’re doing has been tried before and trying to save you frustration, dollars and lost boating time.
Feel free to call if you want to discuss further Joe eight six O eight 83 six 8 nine six

Lots of blade surface area

Fasterboatman

Well of course bravos are not the best choice! There is some sanity to my madness: Im running modest HP and TQ for a 572: 4800 rpm hp=655 tq=702. Of course this is dyno, so remove 15-20% for parasitic losses etc. So Im right at the edge of survivable. The engines were built for durability, and low end torque on regular pump gas.

I did look at the Arneson option pretty hard, but the CFO was clear that she did not want pointy things that close to her or the grand-kids....

I have had discussions with Konad and their ACE drive conversions. They allow you to bolt an extension box, tranny and one of their drives directly to a bravo transom assembly without having to remove the engines. I like the Konrads for their brute strength, but techs are few and far between. If I cant keep my bravos on the water, then I'll just have to get the CFO to see the value of such an upgrade to the konrads....At least that is my plan! Or maybe I am a bit crazy.....

As always, thanks for the valuable feedback.

-j

Fasterboatman

That is gorgeous! I looked at a similar setup that was running on Lake Cumberland in KN. Very fast! But I could not get the CFO past the point bits hanging past the swim platform.

47EXCALIBUR

Thats my old boat in Lake Cumberland with the Arnesons. Most HP i could run through the B3 XR drives was 650hp. The gears would start to pit in 35hours of use. With a 2.0 ratio and 28pitch B3 prop set up she would run 59mph on GPS. Then I got crazy and put a pair of 1150HP engines in with Arnesons and she will run 80 and cruise all day at 50 mph @3500rpm. If your running a B1 xz I would go to a B3XR 2.0 ratio set up and run a 26 pitch prop and call it a day. Good luck

Rookie

iTrader: (4)

I don't believe you'll ever be able to plane the boat with Bravo 1's. Your going to need the dual prop B3's.

Fasterboatman

You very well be right. I will test a few more props, and we will see. The 5 blade should work according to Brett and Bblades, but he is also a bit skeptical of the b1s.

Fasterboatman

Yeah, that may be my only route is to go back to the B3 lowers. I have a pair, they just need yet another rebuild. Sometimes it is cheaper to buy new ones versus rebuild. But that is an option.

I have contacted Konrad to see if they still support the Bravo ACE drive extension. The wife will just not accept the Arnesons.

BDiggity

i bought a used ace pair from the classifieds within the last year & konrad has been great with sending me all of the documentation, drawings, etc along with selling me the tailstocks & transmission mounts i needed. Does take a little time as i think they have to get it in the manufacturing pipeline.