PDA

View Full Version : How much engine can I put in my 16 classic



cfkingfish
05-18-2004, 04:06 PM
Hello-

Im new to the forum, and just purchased a '94 16 classic, and hope to go and get it next week down in Ft Myers. It has the 4.3 with the Alpha One outdrive, and although it has low hours, I may think about yanking the whole system and putting something bigger in. I know that the 5.0 was an option for the classic, but I heard I can also put a 5.7 in also. Is this possible? If I do this, can I keep the Alpha 1 outdrive, or should I upgrade to Bravo? I heard that if you go over 300HP that Bravo should be the way to go. If I can get the 5.7, can I keep the same silent choice exhaust, and where can I find a good 5.7 block for marine use. Im pretty good mechanically with cars, just don't know how to find/setup engines for marine applications. Thanks in advance for any info.

-Christian

Rodger
05-18-2004, 04:28 PM
I have a 16' that I run a SB 406 in with an Alpha drive. I never checked the HP but it runs 72 to 75 MPH. I did break a tooth off a gear in the lower case once. I don't know if it was because of the engine or just a coincidence. As a rule I don't use full throttle to get out of the hole.

slick
05-18-2004, 05:11 PM
My 1997 16' Classic came from the factory with a 5.7 Alpha Drive added Corsa Thru-Hull last year and it runs a true 60 MPH on GPS every time out, now if you really want to get some serious speed out of this package wait for Rootsy and Sam to add their 02's............. :yes:Still up For Sale.........

Rootsy
05-18-2004, 05:30 PM
a sbc will bolt into a 16 without much issue.. a member here, BURTON, replaced his 4.3 with a 5.7 last year... it will be TIGHT against the rear seat bulkhead... the 5.0 (305), 5.7 (350), 383 or 377 and 400 series engines are all the same dimensionally on the outside.. so in reality.. if you wanted to just GO BIG you could plop in a 472 sbc with a supercharger and an arneson and have at er... but you best reenforce stringers and transoms and such.. and make out your will.

but to be realistic... if you are easy on the alpha out of the hole there is no reason you can't get away with 320 - 330 pshp... you aren't pushing a lot of weight.. and keep it in the water too... airborne manuevers can hurt the wallet.

problem with the 16 is chinewalk at high speed... this is due to various factory including CG, weight, bottom design, Length to beam ratio.. yadda yadda yadda yadda yadda... even in stock condition my boat sucked... a lot of this has to do with prop selection and drive depth... as you increase speed it gets more on the edge.. seat time will help you dramtically to conquer it. eliminate as much play as you can in the gimble... just for starters

a short drive such as an Alpha SS is an instant 7 - 8 mph increase.. my handling increased dramatically...

as far as HP.. well i have somewhere in the 400 or a bit more range under the hatch... with an alpha SS and a 4 blade and i've seen pretty close to the 78 mark... if i went to a 3 blade and i could hang onto it (it'd be a ride i think) i am 99.999% positive i'd eclipse the 80 mark... heck i might do it with the 4 blade with some more tweaking...

as far as building a sbc marine engine vs an auto engine... we can discuss all that later i reckon... i have to pack for AOTH now :

JR - agitating the rodent some more :yes:

Marlin275
05-18-2004, 05:33 PM
Marine 5.7
Got mine here
http://www.marinepowerusa.com/

cfkingfish
05-18-2004, 06:14 PM
I think I would go with a 5.7 - now this will mate up with the Alpha One without a problem? Im not too familiar with the Alpha SS, are you talking about a prop or an outdrive? The 5.7 is so easy to get parts for that I figured its the best way to go. This is going to be mainly a saltwalter boat, so Im also thinking what I should do to reinforce the stern, if at all, to accept this application. I definitely would like to hit the 70mph mark, right now itll do 56-57 with one person on calm water.

-Christian

cfkingfish
05-18-2004, 06:16 PM
By the way, what is AOTH? I must be pretty oblivious.:rolleyes:

Ed Donnelly
05-18-2004, 06:32 PM
Try a 350 7.5 to 1 comp. twin turbos, 270 with a speedmaster.put a pad and step on the botttom.
run 18 P.S.I. and a set of Victory tabs and you are good to go...Ed

Dr. Dan
05-18-2004, 07:07 PM
:cool!: Alpha SS is an Outdrive....that moves right along...

AOTH is short for "Awakening Of The Horses" this is the 4th year for the Event....check the Event Section. It is recognized as the First Donzi Registry Crowd Event in the late Spring...normally in May..... Thus far it has been held at Lake Cumberland, Kentucky...and is a Great Cure All of Winter Donzi Cabin Fever for those of us that have a shorter boating Season :D

The Events that are listed...are terrific ways to meet some new best friends....and learn alot about your Donzi.

Good Luck with your Toy.....

Doc :shades:

Mark Albers
05-18-2004, 07:48 PM
Christian :wink:

Welcome to the harbor

Mark :cool:
Sarasota - - - WFO (close to the factory and far from a dream)

cfkingfish
05-18-2004, 08:11 PM
Mark-

Im going to guess you have a Donzi yourself, it just doesnt say it in your signature. I was counting on taking the 16 up as far as Sarasota, and as far south as Naples.... maybe, but only through the ICW. What do you think of this?

-Christian

Mark Albers
05-18-2004, 08:21 PM
Crazy Canine ;)

$20 will go a long way

Now brake out some of that secret seafood dip :biggrin.:

Mark :cool:
Sarasota - - - W F O (close to the factory and far from a dream

Rootsy
05-18-2004, 08:37 PM
Alpha SS = a hi-perf first generation alpha from the late 80's... kind of rare but they can be found... the SS is 3 inches shorter than the alpha and alpha gen II. you have to do some machining to the transom assy on a gen II to make it fit though

a 5.7 (350) will slip right in that boat and you won't have to touch the transom at all. you WILL have to get the sterndrive regeared to a V8ish ratio... like 1.47:1 otherwise you are gonna be spinning some MAJOR pitch props...

you will have to relocate the front motor mounts if i recall correctly.

and as i said the front of the motor, ie, the accessories will be CLOSE to the back seat. i am with holding photos so i don't frighten you ;)

it isn't that bad at all... i highly recommend it if you want a V8. lose as much weight as yu can off of the end... and unless you go to some serious hp or an alpha SS or bravo w/ imco shortie you are gonna be HARD PRESSED to see 70... at least at a controllable level...

350 crank hp should get you 64 - 65 mph...

cfkingfish
05-18-2004, 08:56 PM
[QUOTE=Rootsy]and as i said the front of the motor, ie, the accessories will be CLOSE to the back seat. i am with holding photos so i don't frighten you ;)

[\QUOTE]

Please dont withold pictures, If I had it my way, my motor would be sitting shotgun :D .

-Christian

MOP
05-18-2004, 09:35 PM
Anyone got a shot of the 16 with the blower and the three foot tabs, I think they said that ran 90.

bjh517
05-20-2004, 03:17 PM
I have a 1994 16 Classic. I had a 4.3L, but I put a new 350 Magnum in a few months ago and changed out the gears. I am still propping it, but I love it so far. It is no comparison to my old engine. It scares me once in a while, but I'm learning to handle the porpoising and chine-walking. It was a tight fit, but no modifications had to be made.
I can tell you that comming from a 4.3, you will be thrilled with any small block V8 you choose.
Good Luck!

transman
05-20-2004, 03:51 PM
Thanks to MOP for helping me with this install. He also helped me with the fuel tank.

Forrest
05-20-2004, 04:45 PM
I found that with the 16 Donzi - especially the 16 Donzi - the best foumula to go with is the the least amount of weight at the transom with the most amount of power. For that reason, the combination that I like is a built 302/5.0L Ford engine (much lighter than a SBC), aluminum exhaust, and an AlphaSS drive unit. My little 302 produces about 290HP (Engine Analyzer v3.1) and tops the '72 16 over 70 MPH with little problem. A 347 stroker kit in this block would probably work wonders for bringing the speed up some more, but I'm fine just where it is.

MOP
05-20-2004, 08:38 PM
Thanks to MOP for helping me with this install. He also helped me with the fuel tank.

Tim with the price of gas you will now be the envy of all the other D Net members, so it will cruise 23 and top out at 34 :checkered you will only burn 1-1/2 an hour!

MOP

Rodger
05-21-2004, 08:32 AM
Forrest,
You sure are right about the weight difference between Chevy & Ford. My 16 originally was a SB Ford. When I put the SB Chevy in, the back end floated about 1.5 inches lower. A 289 Ford is almost 100 pounds lighter than a 283 Chevy.