Looking for speed, need the right places

[onesubdrvr]

First, let me say how glad I am to see an active board for people sharing any common interest.

My first boat ride as a young lad was in a Donzi - I believe a 3+2. Anyway, ever since I have been in love with the beautiful lines, and that memory. Until recently I had a 24' Century, but have sold it and purchased an 1988 21' Regazza BR. This boat is about perfect for me now as I have 4 girls in the house plus momma. My desire though is to give it some more 'nads in an attempt to bring it closer to true Donzi performance. It currently has the OMC 4.3L 205hp 800 series outdrive. Any modifications would be considered, including a complete engine / drive swap. How large of an engine will fit without breaking the boat in half? Is there bolt on performance that I can add to this engine, if so, where do I get it?

Thanks in advance for any replies.

"Desperatly wanting a 28zxo"
Wayne
:flag-navy

[MOP]

Being an old OMC mech you have the right idea dumping the 800, it was nothing more than the V6 outboard gear case adapted to a stern drive. My opinion due to availability would be go over to a Bravo and a beefy small block, there are few some off the shelf 383's that should get you a little past 60 top end and make you smile. You are probably looking at 10K to get it up and running. If your pockets are deeper take a hard look at the new 6.0 Crusader, that hooked to a bravo would satisfy most anyone.

Phil

[TuxedoPk]

Phil do you really think putting another 10k or better into a 1988 21' Regazza BR is a good 'investment'?

My personal opinion is to enjoy that boat with little further investment in order not to take a bath come resale time. If I had that boat and wanted to invest $10k more I'd probably sell the boat and purchase a different Donzi with the combined proceeds.

[RedDog]

you have a tuff but rewarding situation. 4 girls plus momma plus perfornance boating is a hard mix. Maybe selling what you have and getting a lower cost (older) Classic for you and a deck boat or something for the family?

I wouldn't recommend building up what you have.

[MOP]

Phil do you really think putting another 10k or better into a 1988 21' Regazza BR is a good 'investment'?

My personal opinion is to enjoy that boat with little further investment in order not to take a bath come resale time. If I had that boat and wanted to invest $10k more I'd probably sell the boat and purchase a different Donzi with the combined proceeds.

NO, but thats coming from me who is doing just that and more to an 1986 :bonk: I did have that same thought about his question. Wayne seems to be looking forward to about a 7 foot Jump maybe sooner than later. Question would be how soon, I will keep mine a long time which helps me rationalize my pit. If Wayne is going to move up within the next 2-3 years a swap to a stock 260-300 that should provide enough gusto and it would increase the value of his boat. I know even in the non performance end of boats the V6 is not easy to sell, where as a V8 will draw a better buck. We can turn this many ways it is up to Wayne :confused:

[onesubdrvr]

To all,

Thanks for the response, I guess it would be a good idea to maybe clearify a bit more. I will probably have this boat atleast until the two oldest girls get to be early teens. Right now they are 9, 8, 4, and 1. I am also currently having a house built which is why I bought a used Donzi vice a new one. When the girls get to their pre teen years, I can see that they will spend less and less time with momma an me, and more and more time with their friends. After reading everyones post, I might be better off milking some performance from this engine, in the mean time look for a block / outdrive that I can rebuild and install at a later date. Not to say that I know everything, but I am a well versed mechanic, and am not opposed to getting a engine needing work to install.
To sum up, I guess looking at performance investments for this engine is best (short term), but what kind of engine swaps could I do that would require little modification to the hull / transom / stringers etc. I definately don't want to make modifications to these on this boat. In my opinion that is where it gets to outweigh the value of the boat.
I guess my ideals would be to keep this boat for 5 years, at that time look at a new donzi, then later, keeping that boat, buy a 30' - 40' boat that momma and I can use for weekend cruises to nowhere, or eventually cruise the great loop.

Thanks again, you guys are great
Wayne :boat:

[olredalert]

----------I agree with the Poodle. A 4.3 shares the same motor mount position as a 350, I believe. Also should share the same exhaust holes if so equipped. The switch is very easy with the possible exception of hatch room, and that could just be a bit of glass work. Good winter project. As Poodle says a salvage boat would be ideal because your engine would have all the small stuff hanging on it, plus you will get the right drive ratio in your outdrive. You would also have your set-up to resell which would go a ways towards paying for someone to do the job if you dont have the time or desire.
----------Oh, dont get crazy with horsepower thoughts. You want to be able to always get all them women back to the dock!!!!!!!..............Bill S

[BUIZILLA]

I did this same swap on my 1990 Four Winns from a 4.3 to a 5.7 arrangement. I was extremely happy with the results. I had the Cobra drive though.... the 800 is your stumble point...
the 5.7 is about 2-3" wider due to the manifold girth, overall arrestor height and motor mount position was exactly the same. The exhaust outlet width is exactly the same on centers. You need the 2 elbows from a 5.7 if it's a thru-prop.

hope this helps. JH

[onesubdrvr]

Once again, thanks to everyone for the input and ideas. I think I'll start looking for a 5.7L unit and start rebuilding it. If I can't find the right package, I'll just consider leaving well enough alone and waiting a couple of years until I'm able to talk Momma into a new one.
Just as an additional question, has anyone heard of these bolt-on marine superchargers? they are supposed to add 35% hp to the engine I have,...is this a viable option?

Thanks again,
Wayne :moped:

[Lenny]

Wayne, I don't think a Pro-Charger on a Regazza is the way to go... Say your money and GO FAST in an INTENDED GO FAST HULL...

...my $.02 :D

[olredalert]

Wayne,

-------A supercharger puts a hell of a strain on a brand new high-perf built drivetrain. Just think of the strain it will put on your little base-perf 4.3. Im sorry, dont go there!!!!!...........Bill S

[onesubdrvr]

Well, I definately appreciate the input. Like I said in an earlier post I think I will just find a 5.7 motor, tear it down, rebuild it, and put it in. I feel more comfortable with doing that. Can someone explain the difference in a Cobra, King Cobra, and any other series outdrives? which would be best for me?

Thanks again,
Wayne
P.S. what about Nitros? (just kidding)