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Quote:

Originally Posted by in the red (Post 3912417)

should have posted on this one earlier but haven't been on the forums much.
2006 28zx with 350 mag mpi's and 1.65 bravos from the factory. Also have factory k-planes.
Drives measure 6 3/4 bottom 6 1/4 top at the center of the gimbal
props turn out per the factory stickers on the transom

boat came with 25 mirage plus's and as vette found they were hard to plane but top end was good, about 71.

I have tried 26 hydromotives and various 26 bravo's labbed and unlabbed. I bought a set of merc labbed, polished 26 bravos on e-bay and ran them for 2 summers and loved them. Great planing, you cant blow them out even if you try. Getting 69 top end consistantly at 5200 rpm. Doesn't really matter 1 or 2 people in the boat. Best top end a shade over 70.

Decided to send them to b-blades the spring of 2012 and ran them last season. Brett said they added more rake to help get the bow out of the water. I also had them do the brushed finish because they told me it was faster than polished. The trim does seem to react more as brett said it would. Bottom line is i really haven't seen much difference in speed. Getting pretty much the same numbers as above. They looked great when i got them back and i don't fault b-blades, i just think maybe i have maxed out what my boat will do with the power it has. These are the right props for the boat. I also run a lot at night and with the k-planes tweaked i can stay on plane at 24-25 mph which is great.

you need to try a set of revolution props...lots of positive results with the donzi hulls..

Thanks Fixx. I have kicked that around from time to time but if I remember correctly the most pitch they offer is a 25, and I didnt think that was enough.

Quote:

Originally Posted by Trueser (Post 3902492)

can you ask him how much cup ? Just got mine back...

and you really need to run a set of Mirage Plus 25. Not the standard Mirage.

But I am curious about your numbers.

You turn them in still?

MIke

Hey Mike,

I didn't get much back from them when I inquired... Here's a snippet from the e-mail:
"We do not send out data sheets with the work we do.
After researching your file I can tell you that we did add rake angle VIA a bend in the tips and a specific amount of cup heights.
I hope this helps answer some of your questions."

I did notice that my props actually turn out though... Someone showed me the old 'put it in gear, and see which way they turn trick...'

Unfortunately... I didn't get to test top end numbers - see below

Quote:

Originally Posted by VetteLT193 (Post 3903293)

FYI: you need to be a LOT more careful as they aren't just a little more fragile, they are a lot more fragile. i.e., you hit bottom and the blade ends will fold in like a tulip.

Aaaaand, I learned this first hand about 1 hour after putting the boat in the water for the first time this year... :poopoo: Me, my fiance', her sister, my sister, and one of their friends cruised over to this little bay we'll hang out in from time to time and it would appear that area is more shallow than I ever remember it being. We hit rock or brick (someone told me once that a bunch of bricks were dumped and spread there years ago...) when coming off plane and I knew right away that I had screwed up pretty good. Once we anchored, I raised the drives all the way up, leaned over the back of the boat, and ran my fingers over each blade... chewed up! :angry-smiley-038: And when I put the boat back in the lift later that night, I saw that my freshly painted lowers had been banged up too... *sigh*

[ATTACH=CONFIG]501965[/ATTACH][ATTACH=CONFIG]501966[/ATTACH]

Live and learn I suppose...

We had a poker run to participate in the next day, so I (reluctantly) swapped over to my brand new Bravos the morning of. In an effort to keep this post "on topic" I can say that I experienced the same thing that everyone else has talked about with those 4-blades... The boat now takes off and planes without any effort at all... very responsive in the mid-range, and still turns tight and with ease. I did lose about 300-500 RPM and my speed topped out at 74 on GPS though... someone told me later that day that those props were too big? Not sure... 15.25x28 Bravo 1

- justin

Ok, Finally got on the water... what a crappy spring... anyway I ended up sending my 23's in to get labbed I am now turning 5k and top speed is 68 on GPS... best ever on my boat.

Quote:

Originally Posted by Dukedonzi (Post 3940562)

Ok, Finally got on the water... what a crappy spring... anyway I ended up sending my 23's in to get labbed I am now turning 5k and top speed is 68 on GPS... best ever on my boat.

Where did you send them?

2004 zxo with 350s and mirage plus 23s. Just got them back from a local shop because was having some blowout issues. Boat runs much better but best I could get get out of it was 60 gps. Interestingly enough, props spinning out but the decals indicate to spin in. Would it make that much difference? I expected the boat to run around 70 with that setup.

Quote:

Originally Posted by JRalston (Post 4557548)

Something is not rite, You should be getting 70

Quote:

Originally Posted by Trueser (Post 4557556)

Something is not rite, You should be getting 70

I'm going to switch them tomorrow

Zxo boats don't run as fast as regular zx. The open bow nukes speed pretty good, according to a former donzi test driver it is aerodynamics.

Scorpion zxo will kiss 73, 6.2 Zxo can get to 70. 350 Zxo 65, maybe 67 or 68.

With 6.2's I can run mid 60s with bravo 1 26 or bravo 1 24s. Does the same speed at different rpms. Keep in mind I have 1.65 drives so a 350 boat with 1.5 drives needs a lot less wheel. I am spinning in.

I really cant run mirage plus props. It's a safety concern... with where I boat we get afternoon BIG rollers and the boat is near impossible to plane. With bravo 1s we just go.

I might lab mine this year, time will tell;) I'm guessing a good lab bravo 1 24, add cup and an inch, will net me 70 daily