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aeversole
08-28-2005, 12:03 PM
I have an older (1987) Donzi Z22 that I have repowered with a Supercharged 454Mag. and Bravo drive. The boat did not come with trim tabs and currently runs out very smooth at 75+ mph. However, at cruising speeds it tends to porpose quite alot. I am looking for suggestions as to how to correct the porposing. If tabs are the recomended fix, whitch brand and model would be best for this particular model and length donzi.

joel3078
08-28-2005, 12:31 PM
Welcom to the Donzi board Aeversole. I'm pretty new here myself. I have read over and over the following for 22' Donzi's. Get a Turbo brand prop and Bennett (spell?) tabs. This combination works very good or maybe even best to reduce your front end bounce. At minimum, install the trim tabs! This will get you on plane faster, control bounce, and actually give you faster top end speed.

Trim tabs
http://www.bennetttrimtabs.com/

Turbo prop
http://www.turbo-props.com/

RedDog
08-28-2005, 04:58 PM
Do you mean a z21 or 22 Classic - here is a Z21:
http://www.donzi.net/photos/osaffell617.jpg
- see the model list tab at the top right hand of your browser.

The Turbo prop recommendation may not apply to a Z21. Trim tabs would help.

Lenny
08-28-2005, 05:19 PM
RD, I believe they renamed the Z22 to a Z21 in 1988. That could be the confusion. I remember the porposing that Eric G's would encounter at cruising speeds and he had a small block for weight.

I think that tabs would fix it to a large degree. 12" x 9" chord would be sufficient I think. Ask "Tabman" (Bennett Marine)

GG Donzi
08-29-2005, 02:38 AM
I have an 18 Classic which porposes at times? I quit beating myself up trying to figure out why. One though was fuel slouch. It seems once it begans to porpose if I turn either direction it stops until I hit a wave. Just a thought!