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g-tech
06-07-2006, 10:17 PM
I bought myself a 92 Classic 18 as project boat. I own my own custom shop were we do fiberglass/gelcote/metal work among other things so I really want this boat to be little project to will represent the professional work we do. After regelcoting the whole boat what do I repower with? It has a King Cobra with a 351 now and I have pretty much decided that the cleanest approach is to buy a sterndrive package with drive, motor, gimbal, transom assembly, motor, manifolds, and belts hoses etc. I won't put an alpha on it and I'm thinking 5.7 or 6.2 liter efi motor then If I need more power I can stuff it with a pro charger. I was wondering if the new volvo duoprop or bravo 3 would be good on that boat? I never see duoprops on real hardcore performance boats but I think it would have a nice "wow" factor plus I'm thinking it would help the tracking and stability. Also does anybody know if the King Cobra transom hole is similar to or smaller than any currently manufactered drives? If would be shame to redo a perfectly good transom if you didn't have to. The options or endless interested in pro and cons or any feedback. What would you do?

G-tech,
G-tech motorsports, LLC
g-tech@verizon.net

pmreed
06-07-2006, 11:00 PM
Check out the Mercruiser 383/Bravo package. About 9K I believe. 350 hp with a warranty. Contact the Harbormaster...boat parts are his business.

Phil

realbold
06-08-2006, 04:49 AM
Bravo 3, Duoprops get squirrelly at speeds over 70 mph which is probably why you dont see them on performance boats.

Morgan's Cloud
06-08-2006, 07:06 AM
It's too small for a 2 prop unit IMHO !
The B3 is a bit different than the Volvo DPS (which is all you'd need at the max ).
If you MUST do the 2 prop unit you'll get better performance with the Volvo.
Incidentally , it's a bit of a generalisation to claim the 2 prop units as 'squirelly' over 70.... Ever been in a DPX equipped Scarab at over 80 MPH ? Or a DPX rigged Cobalt at 70 ? The last thing they are is 'squirelly' take my word.
This info comes from someone who has both types of units so I'm not taking a guess here .
It will be a fun project , but if it was me I'd otherwise stick with a single prop unit.
Steve

Barry Eller
06-08-2006, 07:34 AM
The hole in the transom is larger for the King Cobra. I re-powered my 22C with a 502 and kept the King Cobra drive. It is a bullet proof drive, mostly Volvo. If you replaced your outdrive with Merc. you will have to redo the transom. But you probably could install a new Volvo. I have driven a Duo-Prop boat before, they handle great. Especially when backing in to a slip.

MOP
06-08-2006, 08:02 AM
The Vovlo would be my choice it has proven its self faster then the BIII, dou's are fantasic at speed gone is chine walk, as is the steeing torque and the side ways landing lurch of a single.

Phil

Carl C
06-08-2006, 08:09 AM
Is your present drive or engine blown? If not I would stick with what you have. The KC drive is tough and the 351 is a good motor. I'd put the money into building that motor and lightening it with aluminum parts wherever possible. JMHO.

rustnrot
06-08-2006, 10:18 AM
I was thinking of buying that same boat but too many projects already. If I had gotten it, I was going with this Lexus ski boat engine and surface drive.
I have two drives, barely used, if you want one let me know I am using one with supercharged rotary power in a formula jr. hull, I may sell the V8, 300 hp all aluminum, 37 hours, DOHC came out of Toyota ski boat.

Pismo
06-08-2006, 12:29 PM
The last thing you need on an 18 footer is a Bravo 3. It will cost you significant top end. The only Wow factor you will get is "Wow, why is that 18 with 350hp so slow?" Dual prop think big heavy fishing boats or cruisers. You can always mix and match, get a Volvo drive so less hole filling needed and a 383 bobtail. If you are going to fill the transom anyhow, get a Bravo 1 and a powerful small block like the 383 suggested.