2000 Z-22 top speed

[the wharf]

Just wondering if anyone has had anyluck on getting the Z-22 bowrider 350mag to a good top speed-I am at 55 mph with a 23 pitch lazer11?Is there a better prop?I had a 23 mirage2 and it took out my lower unit twice!
Thanks

[Ranman]

I'm curious as to how a prop took out your lower unit? Please explain.

[the wharf]

I'm curious as to how a prop took out your lower unit? Please explain.
The Mirage pushes so much water that it is extremely hard on the alpha drive
everytime you put it into gear-The dealers and Donzi marine are aware of this
problem with the Mirages and the Alpha drives?I learned the hardway twice!
thanks

[Rootsy]

just a few questions about the mirage? is it a solid hub? and at what rpm is your 350 idling when you put it in gear? what broke exactly in your sterndrive?

[the wharf]

just a few questions about the mirage? is it a solid hub? and at what rpm is your 350 idling when you put it in gear? what broke exactly in your sterndrive?
It is not a solid hub,The engine idle is at factory setting on the 350 mag
I think 1500?I cant remember-The upper gear tooth broke coming out of the upper housing twice-
Thanks

[Ed Donnelly]

I'm no expert but,1500 sounds a tad high. Maybe 650 is more in the ballpark.
When I was running the F.I. on my big block, I idled at 600 with a healthy cam...Ed

[Ranman]

The dealers and Donzi marine are aware of this

Who is feeding you this information? Is this a dealer telling you that Donzi is aware of a problem between Mirage props and Alpha drives? I don't want to come off the wrong way as I am here to help you the best I can, but suggesting that a Mirage is so much "harder" on an Alpha than a Laser sounds very naive. This is not the sole reason as to your drive failures. There are tons of people who run Mirages on Alphas with no issue. This includes Donzis and other makes too.

As Rootsy is suggesting, if you run a solid hub prop and hit something with it, THAT can cause a gear failure. If your idle is way too high and your dropping the Alpha into gear, THAT may cause a gear failure. THe prop alone is not responsible for the failures, there is something else playing into this equasion.

IF you care to provide any more details on your setup and operating habits, you will get several people here who will offer better suggestions. You can learn a lot very quickly by paying attention to this board and asking questions. Good luck.

Ranman

[the wharf]

Who is feeding you this information? Is this a dealer telling you that Donzi is aware of a problem between Mirage props and Alpha drives? I don't want to come off the wrong way as I am here to help you the best I can, but suggesting that a Mirage is so much "harder" on an Alpha than a Laser sounds very naive. This is not the sole reason as to your drive failures. There are tons of people who run Mirages on Alphas with no issue. This includes Donzis and other makes too.

As Rootsy is suggesting, if you run a solid hub prop and hit something with it, THAT can cause a gear failure. If your idle is way too high and your dropping the Alpha into gear, THAT may cause a gear failure. THe prop alone is not responsible for the failures, there is something else playing into this equasion.

IF you care to provide any more details on your setup and operating habits, you will get several people here who will offer better suggestions. You can learn a lot very quickly by paying attention to this board and asking questions. Good luck.

Ranman
I do remember that the engine idle is at 650-
When this problem happened -It was dianosed as a Mirag plus problem for the Alpha by the dealer and then backed up by Mercruisers technician!
The Mirage plus worked great but after 2 blown gears I switched to the Lazer2-And have had no problems in 1 year of running?Some of the mechanics
say that Donzi or Mercruiser should of put a Bravo 1 on that boat with the 300hp motor?
Any how since I switched to the laser I lost 2to3 mph!
thanks

[Rootsy]

i don't buy the whole mirage breaking the alpha theory... i havn't been to a mercruiser training program in about 10 years but i've had plenty of time with the sterndrives...

idle should be 600 - 650 rpm IN GEAR... which equates to about 750 - 800 at idle if the timing and fuel are set correctly.

when it comes to propellers the mirage is not very radical... i've run cleavers, mirages, hydromotive 4 blades, quicksilvers, etc etc etc on my alpha GEN II... and other alpha's also.

i would equate breaking a tooth in the top of the drive to backlash in the gearset or severe loading and unloading of the drive at high rpm. or, unlikely, but possible, defective gears. if it was caused by loading and unloading at high rpm like you'd see by airing the boat out, etc, you'd likely see a bit of shear on the vertical shaft spline. but as i alluded to a few posts back... high rpm clashing into gear will play hell on internal sterndrive components. you should also run merc hi-po synthetic gear lube in that drive.

if you are concerned and don't want to spin the mirage, that's perfectly fine... a better choice than the laser may possibly be a turbo1 from turbo propellers. they are pretty good performers, generally right there with the mirage or outperforming the mirage. they are a smaller diameter round eared 3 blade... and they are significantly less expensive than the merc propellers.

breaking sucks arse...

Root - toot toot...

[Ranman]

i don't buy the whole mirage breaking the alpha theory...

I'm with ya Root, I don't buy it either. Anyway, moving on...

The Z-22 is a good size boat. There are many 18 2+3 Classics that run a MAG 350/Alpha setup with no problems. The 22 is a significantly heavier boat and thus places more strain on your Alpha than a smaller boat. You are naturally close to the limit of an Alpha One. It's generally accepted that an Alpha One is good up to 300HP. Some folks have been able to run more power through them, but I think most of those people are running smaller, lighter boats and are very careful with the power delivery. As the size of the boat increases, the power handling/reliability of the Alpha decreases. WIth 300HP and a Z-22, you may be right at the limit especially if you drive her hard.

Rootsy makes a good point, the Turbo One propeller is a popular choice here on Donzi.net. Check out http://www.turbo-props.com/Propellers.html. On the Classic series of Donzi's tese props are as good if not better than a Mirage Plus. I would think this would also be the case on other hulls too. If you shop around, you should be able to pick one up new for under $400 or watch Ebay for what you want. Again, good luck in you hunt for speed.

[the wharf]

I'm with ya Root, I don't buy it either. Anyway, moving on...

The Z-22 is a good size boat. There are many 18 2+3 Classics that run a MAG 350/Alpha setup with no problems. The 22 is a significantly heavier boat and thus places more strain on your Alpha than a smaller boat. You are naturally close to the limit of an Alpha One. It's generally accepted that an Alpha One is good up to 300HP. Some folks have been able to run more power through them, but I think most of those people are running smaller, lighter boats and are very careful with the power delivery. As the size of the boat increases, the power handling/reliability of the Alpha decreases. WIth 300HP and a Z-22, you may be right at the limit especially if you drive her hard.

Rootsy makes a good point, the Turbo One propeller is a popular choice here on Donzi.net. Check out http://www.turbo-props.com/Propellers.html. On the Classic series of Donzi's tese props are as good if not better than a Mirage Plus. I would think this would also be the case on other hulls too. If you shop around, you should be able to pick one up new for under $400 or watch Ebay for what you want. Again, good luck in you hunt for speed.
Thank you

[z22owner]

My Z-22 is running a 350 EFI (260 Hp) with thru hull exhaust and a 22P Bravo 1. I have no problem running in the high 50's and have touch 60 a time or 2 in smooth water. I only have 64 hrs. on the boat and drive but have not run into any drive problems. Great combination for the boat.

Z22owner

[the wharf]

My Z-22 is running a 350 EFI (260 Hp) with thru hull exhaust and a 22P Bravo 1. I have no problem running in the high 50's and have touch 60 a time or 2 in smooth water. I only have 64 hrs. on the boat and drive but have not run into any drive problems. Great combination for the boat.

Z22owner
Do you have the Bravo or Alpha lower unit?Mine is the Alpha-with a 23
pitch lazer-55 tops with weight 53 at 4900pm-I have the 300 hp mag?

[z22owner]

Do you have the Bravo or Alpha lower unit?Mine is the Alpha-with a 23
pitch lazer-55 tops with weight 53 at 4900pm-I have the 300 hp mag?


I do have an Alpha setup. I tried many props, including the 23P Mirage, 21P Vengeance (stock prop) and they didnt hold a candle to the 22P Bravo four blade. I really believe that our boat runs best with a four blade wheel.

Z22owner

[Ranman]

I do have an Alpha setup. I tried many props, including the 23P Mirage, 21P Vengeance (stock prop) and they didnt hold a candle to the 22P Bravo four blade. I really believe that our boat runs best with a four blade wheel.

If this is true, the Hydromotive Intimidator Quad IV may be another option. Again, I cannot speak for the Z-22 specifically, but the Quad IV is another popular choice on the Classics. This is a very solid and stable prop that really has the ability to calm a flighty Classic hull. If you decide to try a 4 blade, be warned that they "grip" even harder than the 3 bladers sooo...

Also, if you decide to try a 4 blade prop, be sure to step the pitch down 1 or 2 inches. Example: I run a 25P Mirage and a 24P Hydro 4 blade.