Thinking I need more power!
 

Here is the deal I have a Donzi 26Zx with a 454 (385 HP) and need to get more power out of it. I am contenplating the following:

1) Whipple Charger (cost)
2) Stainless Marine Exhaust
3) Cam

Give me some ideas????

EFI or Carb engine?

Give us an idea of what your objective is. How much faster do you want to go? That will determine how much more power you will need.

Speed cost $. How much do you want to spend. What prop and pitch, drive ratio, WOT rpm and MPH do you have now?

I am running around 4800RPM at 68 mph and my problem is I am running a 1.5 Bravo drive with a 24 pitch 4 blade prop. When I put more than 2 people in the boat it barely planes off. I want the boat to have a good hole shot but don't want to go down in prop size because I don't want to lose the top end. I would like to keep it around 4K or so. Any ideas would be appreciated!!!

Donzi- your goal is admirable and common but you are falling in a middle ground for which there are no real answers. Cam and exhaust can easily eat 4K if you include labor- seat of the pants will show a little- GPS will likely show less(2-4). A whipple is a little over 5k just for the kit (I'm a distributor), no labor, prop, gages, hyd. steering (You will need it with the speeds you see) transom or LWP if you don't have one etc.

In short, I would look at getting all you can from labbing your prop through York which will help some at a minimal cost ($200ish), perhaps a computer reprogram from Arizona Speed and Marine (I'm guessing at 500ish) This will help bang for the buck wise. Otherwise go Whipple, it's not that much more $ than cam and exhaust but the performance difference is awesome. Good luck. you really just need to weigh how much bang you want and what are you willing to pay to get it.

So you think you need more power! Don't you know that's when all the trouble starts? Why can't you just be happy with the speed you've got like the rest of us! :rolleyes:

Seriously, that's a big boat for a single engine, so you can't do anything that will cost you bottom end torque. One step up on the cam and you may not get up on plane at all. I agree with Cattitude, you need to save up for a blower.

Agree with Cat. You're a little under budgetted. You culd do exhaust manifolds and ss risers $2k, MSD ignition, Air filter and ECU reprogram $1.5k. Will probably pick up some low end and 300rpm on the top. You'll hit low 70s then prop work $500. Your $4k is gone.

you could get a used (non whipple) blower the whipples are good but they are pricey.

Off Topic but are you ever at the sanhole in Oyster Bay? Or in Oyster Bay itself? I have seena 26' donzi flyind around a bunch of times.

Yeah, I go over to the sand hole all the time in L.I., I am there almost every weekend. My boat is white with the Red and Black stripe on it. Well I gues I will have to way my options. Does anyone think that just exhaust and a labbed prop will get me a better hole shot? With the 454 Donzi wasn't sure which prop to run, first they said the 24 4 blade and than they changed there monds and told me the 22 4 blade. I tried the 22 but I lose about 6 to 8 on the top end but have a great hole shot. What do you think that the boat would do with the whipple on it, miles per hour and hole shot?

I KNOW FOR A FACT THAT YOUR FATHER IN-LAW WILL UNBOLT YOUR HYDRA-HOIST FROM THE DOC AT HIS HOUSE AND LET IT DRIFT OFF TO SEA IF YOU WHIPPLE CHARGE WITH HIS DAUGHTER IN THE BOAT!!!!YOU BETTER MOVE THE CASE OF CORONAS UP TO THE FRONT OF THE BOAT TO GET THAT SLED OUT OF THE WATER FASTER!!! HOPE MEGHAN IS FEELING BETTER,I COULDNT HELP MYSELF

I will definately put a super blower on the boat now so I can keep up with Moron!!!!! Meghan is doing well thanks!!!!

I think the key here is I want the best of both hole and top end mine 27 avanti 4200lb. 24* v just about same hp I have three props 19 mirage I use only when have big load high seas or just want to make her hop up and **** like a little sports car 21 revolution 4 for when smaller loads and good mid range all around good handeling 23 mirage for top end .for me its what I must do till I win the loto and drop the big bucks on the big ponies. my .01 don't have .02

I AM FINDING FROM EXPERENCE THAT HORSES&MONEY ARE VERY EXPENSIVE FOR LITTLE GAIN IN SPEED. THEIR'S NOTHING LIKE A 454 FOR BULLET PROOF TURN KEY MOTOR.I CAN'T STAND SPENDING THE BIG BUCK & GETTING THE BIG LET DOWN. STICK WITH WHAT YOU GOT.YOU WILL STILL BE RUNNING AT THE END OF THE DAY WHEN WE ARE WRENCHING & SPENDING MONEY TO KEEP GOING. :) ;)

It sounds like you havd a Donzi 26zx with a step hulland your using a Bravo I prop. I would try a different manufacture's prop, maby a Turbo (several different style props) or a Hydromotive. You need sompting with lift. I did some work on a 22ZX and found a Merc Revolution 4 (23 pitch) pulled better than the 24 BravoI in all respects including top end as did the Turbos tried 3 different types. than the owner got tired and quit. Forget the marage plus on that boat not enough srern lift. On my own boat the Turbo lightning worked best along with the Hydro. The Bravos were the slower props I have tried. I have a 22 V hull non stepped Donzi. All my checking was with a GPS and good tach. The exhaust would help with that engine.Remember there are no large gains here just small ones 1->4 mph at best with exhaust and prop.

Randy

[ 01-19-2002: Message edited by: BigGrizzly ]

Mine is the 502, I was STUCK at 4600 RPM, ADDED a lab prop (24 P Bravo I), K&N and went from 66 to 67ish on GPS to a solid 70ish, 70.4 to be exact (5 adults, 2 kids, full tank i might add). We have only been out on the new Donzi 4 times, more info is the spring!
So for a few hundred it made all the difference in the world, especially getting on plane... One person refers to the big heavy Donzi as a tank, I just rev to 3500 and take the extra few seconds to plane, now she jumps up!
Another 26ZX in our club was the same way with a 496Mag HO, Merc racing prop, changed the whole boat running characteristics.
Good luck.
Bryan

PS Wise words from WILDTHING TAZ....
Hi Griz, you can quote me this time. :)
see ya in KY... I know I owe you an email, I hope your well my friend...

[ 01-19-2002: Message edited by: 2001 26ZX ]