ZXXX Donzi

Has anybody tried an extension box on a 26ZX? I would love to know how it likes one.

Bryan Rose

could work.......then again could not work.....I have yet to see a small single v benefit from it yet.....there is one guy I think his name is wildcard or something on a 25 foot Baja....says he picked up a lot with it...............I think it is a crap shoot.....my honest opinion is it is an expensive test to do ....labor and parts to have it not work.....the rig will run into the 90 's no problemmmmmmmmm with the intended HP and drive combo..................save the cash and put on some 380 k planes and buy gas with the rest of the dough you save from not doing it.....

My 2 cents from the man who will be slower than you this year.

Bryan

ZXXX Donzi

I know. I sure would like to know if it has been done though. But you are right, I probably won't need the extra speed

GABLES

Bryan. what do you run your 27 Donzi at? Ive a 26zx and have had handling issues passing the 80 gps barrier. When i fitted 23"tabs and full hydraulic it then moved the problem higher up to 88 gps!(I feel i can now have a bigger accident !!!) I also was thinking of a stand-off box though following the thought of lengthening the boat not for speed gains. My other feeling is that she is trying to walk the prop so was thinking should i bury it! Then she runs easier at max trim, but must trim back in and drop tabs a touch to run past 80 . Was also thinking about ratio change and drop a few inches of pitch. Am running a XR and stock 30" Bravo .Sorry for changing the theme of the thread but i need answers from someone who been into the unknown and returned to tell the story !!!!

Your overseas cousin!!

Trevor

ZXXX Donzi

Hey Trevor,

I have a couple of questions:

Are you needing the tabs when you run at high speeds in your 26? I know that you drop them a touch but do you keep them down or is that just to get past that unsettled part in the high 70's If so, what setting.

What trim setting are you using?

Have you checked your hull for hook or any other issues?

How much thottle do you have left?

I am building up a 26 very similar to your and wanted a couple of pointers. I just bought the IMCO full hydraulic and am looking for tabs.

ZXXX Donzi

Trevor,

I will call Brian about this so he can respond. He is sort of busy these days.

In the mean time, he runs a stock Bravo 30" and a 1.5 ratio. I have driven his boat just nort of 80 and did not need to drop the tabs. I don't think he uses them at 85. He has a shorty but his boat has a lower X dim.

His running surface is very similar to ours but he has a strake that goes all the way to the back after the last step. I will do a total side to side comparison of our boats this spring.

He is doing the heads and more boost so we will know more about how his boat handles as he gets it to 90.

GABLES

Thanks for your reply-you did not let me know your name by the way. I will be posting a reply tomorrow when we have all the figures straight and symptom straight. But will be glad to compare notes and hopefully both benefit from it.

Regards
Trevor

ZXXX Donzi

That sounds good. Are you running up there this time of the year. If is cold enough down here in Tn.

Regards,
Bill

GABLES

Hi Bill. We are UK south coast based and yes it's cold here but we still boat all the year round! We run mainly offshore with someriver use as during winter months speed restrictions lifted.
Back to Miss Donzi - she is a 2001 model with 2 steps and pad at rear. X dimension is 2.5". She runs a self modified 502 mpi fully balanced, extreme cam, alloy heads, performance headers and remapped ECU, with M3 procharger. She runs on the limiter 5400 rpm showing 7psi with 3 crew and 60 gallons fuel. Have seen 88gps but chickened out and pulled back whilst she was still building speed. Consider 90mph plus possible but for handling issues! Am running 23" tapered Hardin Marine tabs, WPM full hydraulic steering. At near max speed run trim back into 3, run tabs flush with hull - she feels happier trimmed at 7 - seems to free up more. Always spins prop up. We had issues previously at 78mph but tabs and steering it moved to higher figure - felt tabs made biggest influence which is why consider could be bigger. When running in flat water at 80 feels as though she is walking around at rear, or with additional severe chine walking - as if trying to walk the prop which was my next thought to change ratio and swing less pitch.
Anyways Bill I'm lost till I find someone who has been there and come back!!
What do you reckon - Regards Trevor

ZXXX Donzi

Thanks for the feedback Trevor. I have heard of the 26 hull being taken to 105 with huge power. I heard that it is good to 95. This has not been confirmed. I read a post of a guy that took it to 92 and got scared stiff.

You have one serious setup. That is pretty impressive. I can appreciate that you are stepping up to the plate.

Hmm. I really appreciate your input on the tabs. It looks like I will need 30". I will be running a 540 configured very similar to your 502. The engine goes on the dyno in about 3 weeks. I am running stock X with an IMCO lower.

Mine is a 99 and I think it has the same hull as yours. I will go over to the boat this weekend with a laser and a straight edge to make sure it it dang straight. If I find anything I don't like I will take it to the glass shop while it is still cold. Give me 6 weeks or so and I will be a test pilot along with you.

Have you considered some different props? I don't know but it is always worth a shot.

Thanks for your feedback,

Bill