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Z-Man
06-19-2006, 06:37 PM
Anyone have recommendations for a 28ZX with twin 350 Mags(300hp)/B1(stardard ratios)? The factory props are the three blade Mirage 23 pitch which do fine but I am looking for a little more bite. I just spun a pair of 25 pithc 4-Blade Hydromotives that hooked up well in the mid range but blew up frequently at slow speeds (Presuming I do not have enough torque to turn them). Hitting nearly 5000 RPM at WOT with the Mirages. Thanks.

Mr X
06-19-2006, 07:48 PM
When I worked at Donzi, we spent several days on the water propping the 28ZX. We tried EVERY prop made. The 23 Mirage plus is THE prop for that boat.
The X-dimension is very high on that boat, and the twin step hull design make the props easy to cavatate when comming out of the hole. Just be easy on the throttles and you will not have a problem. If you are looking to pull a skier
then you might try a set of 21's.

BigGrizzly
06-20-2006, 07:21 PM
I don't agree with Ted, Try other props I havn't found a boat that I could not beat the Marage pluss with a different prop. Marage was a good prop years ago but tha was history. come to Eufala or Lake Lanier and we can test different brands of props.

The Hedgehog
06-20-2006, 08:09 PM
I don't agree with Ted, Try other props I havn't found a boat that I could not beat the Marage pluss with a different prop. Marage was a good prop years ago but tha was history. come to Eufala or Lake Lanier and we can test different brands of props.

Hey Randy,

How often to you get over to Eufaula? I think that Dawsonville is pretty close.

Mr X
06-20-2006, 08:16 PM
I don't agree with Ted, Try other props I havn't found a boat that I could not beat the Marage pluss with a different prop. Marage was a good prop years ago but tha was history. come to Eufala or Lake Lanier and we can test different brands of props.

Randy, let me know how you guys make out with the testing....
I am always looking for something better.
If you are going to have a large selection of props available there for testing, I would like to try them all on my 28ZX Scoropion as well.
Let me know.
Thanks
Ted

mlg44
06-20-2006, 10:52 PM
Hey Guys,

I also own a 28ZX Scorpion & would like to know the outcome of the testing. Please let me know. Thanks, Mike

Mr X
06-20-2006, 10:58 PM
Cool! post a couple of pictures of your Scorpion!

BigGrizzly
06-23-2006, 07:44 PM
I usually come down for the Eufala only because I have my dream house here on Lake Lanier with hydro hoyst and all. I would like to do the prop thing at Eufala since That is what I usually do anyway. Ted I would like to bring some stuff down. Testing props is fun especially at Eufala especially do to lack of traffic. As we get closer let me know about what sizes to bring and we can go from there. Brsides we should test props that may or may not work just to really prove it. There are too many "it won't work" statements that have never been tried. My current Ctiterion engine is one of those. You know wrong cam wrong carb(too small) wrong pistons bad block etc. My boat almost can't get out of its own way with that outboard prop on it. The only problem, no one told that to the GPS!!! Theory is good but honest testing TRUTH. Ted it would be good to see you again. Just so everone knows I am retiring from HONDA on June 30 2006, and will concentrate on my prop business and go back to building a small amount of motors with Garry Grimes. He does the work and I turn the Key LOA.

Z-Man
07-05-2006, 07:07 PM
Sorry for the long delay in responding. I tried to spend an entire summers worth of gas money in two weeks between Grand Lake and LOTO. I would be interested in coming down to due some testing if we can find a convenient time.

Scorp
07-05-2006, 07:59 PM
Hi Mr. X,
Thanks for your expertise on these Z-boats.
I have had thoughts on trying something other than the Mirage+ 25P props mine came with, but am satisfied now from your comments that I should stand fast.
I wonder if those fancy new props Mercury has come out with will eventually be manufactured in our size, and then offer real improvement over the M+ in SS.
One note [or question to ask you if you know an answer], is why Donzi changed the counter rotation of the props from outward, to inward on our later models. How did this change performance ? My '00 is outward rotating.
Other later '00s are inward. I am also aware of a slight hull change on the '00 28s, but mine is the latter model of those.
Thanks again for all your input.
Cheers !
Hope you are having a GREAT summer....I am.

BigGrizzly
07-05-2006, 09:02 PM
Z-man Let me know about when you want to do thisand I will get several combinations together arounf your current prop size. The object is to get the best all around performance and top speed together, Difficult but not always impossible I think we can do this with your boat.

Mr X
07-05-2006, 10:09 PM
Hi Mr. X,
Thanks for your expertise on these Z-boats.
I have had thoughts on trying something other than the Mirage+ 25P props mine came with, but am satisfied now from your comments that I should stand fast.
I wonder if those fancy new props Mercury has come out with will eventually be manufactured in our size, and then offer real improvement over the M+ in SS.
One note [or question to ask you if you know an answer], is why Donzi changed the counter rotation of the props from outward, to inward on our later models. How did this change performance ? My '00 is outward rotating.
Other later '00s are inward. I am also aware of a slight hull change on the '00 28s, but mine is the latter model of those.
Thanks again for all your input.
Cheers !
Hope you are having a GREAT summer....I am.
Scorp,
beautiful boat! Mine is the reverse color of yours.
All of the Scorpion edition's had inboard rotation. It is good for 1.5 MPH top end........but only on the Scorpion's. We were never totally sure why. The outboard rotation handles better around the dock and is easier to drive at top end though.
I wonder why yours has outboard rotation.....are you the original owner?
It should have 25 Mirage plus LAB props. Are your props labbed?
Randy, I hope to see you soon. Congrats on the retirment!!!

Scorp
07-05-2006, 10:49 PM
Hi again Mr. X,
Thanks for your reply.
I am not the original owner, but believe I am #2.
This is 28' hull #37, made in February 2000.
The screws definately turn outward......
The M+25s are not labbed.
I believe my B1s are 1.36 ratio.
I am getting >5000 rpm at WOT, so labbed would probably hit the rev limiter.
This boat still runs as good as it looks !
I hope yours does too. The reverse color scheme you have is awsome.
These engines are so sweet, I don't even mind feeding them premium :shocking:
I hope you enjoy beating Fountains as much as I do with this boat.
Thanks,
Steve

Mr X
07-05-2006, 11:03 PM
Scorp,
I tried 1:36's totally by mistake.....and only pulled 4600 RPM's with labs.
You definatly have 1:50's no question. Labs on our boats are good for 250 RPM's. You really should get a set of labs...All the Scorpions came with them.
Mine runs just as it did on day one. Actually a little better now with the exhaust and the XR drives.
I actually watched mine as it was being built when I worked at the factory.
The 28ZX Scorpion is my favorite Donzi!