2 stroke to 4 stroke conversion help PLEASE

[trtdds]

I am thinking of upgrading my 1996 20' Champion Coastal Champ from it's original Mariner 200 HP 2 stroke to a new 4 stroke outboard. My boat is rated for 225 HP. Will I get the same performance with a 225 4 stroke as I get with my 200 2 stroke? If I need to get more HP to get the same performance, which of the manufacturers are using detuned 250's or 300's as their 225, and how hard is it to retune to higher HP? Which 4 strokes are best for salt water. Any help you can offer will be appreciated, as I am having trouble getting staight answers from dealers and manufacturers. Everyone I have talked to has told me there will be a decrease in performance, but no one has told me how much performance loss I will experience. Thanks for your help. If you have personally refit from a 2 stroke to a 4 stroke, PLEASE let me know about your experience.

[weedeater]

Have you considered merc opti or merc xs and staying with 2stroke?

[trtdds]

I also use the boat in National Park waters out west and they are going to be prohibiting 2 strokes in the near future. They have all ready banned all 2 stroke personal water craft (wave runners, jet skis, etc.), outboards won't be far behind, so I will have to go to a 4 stroke. It's a family vacation thing and attendance is mandatory!! I'd love a new 2 stroke, but it's not in my future.

[fishaholic82]

I would think that you shouldn't really see a difference due to the fact that outboard horsepower ratings are no longer measured at the flywheel and are now measured at the prop. When we re-powered an old skiff that had a 97 yamaha 50 with a 2010 yamaha 50 4 stoke it was faster than the older engine ever was.

[flounder_smacker]

If you can run a 20 inch shaft I would look in the Yamaha vmax sho. Not sure if you are looking for a new motor but the new yamahas are better than the two strokes.

[BaseballFisherman]

I am picking up my new boat this week and I went with a Yamaha VMax SHO on it. I'm like you, going from an old 2 stroke to a new 4 stroke. The SHO is performing with the best of the 2 strokes right now and even out performing some of them. I'm sure if you go with the SHO no matter if it is a 200 or 225, you will see a performance increase over your old motor. I would figure any newer four stroke of the same horsepower would give you a little extra performance over that older motor. The bad thing about the Champs though, is that they aren't built for speed. I just sold my 21 Bay Champ. It rode like a dream but people with 100 more horsepower than me on the same boat were only running about 8 mph faster than I was. I think the coastal champ hull is similar to the bay champ so I wouldn't expect any huge gains in speed. The newer outboard should definitely help your fuel bill though.

[eman]

just remember the weight differential ,between 2 stroke and 4 stroke.

[Saltysacalait]

I'm a 2 stroke man but u will be satisfied w/ the sho. Prop setup and weight distribution is everything.

[trtdds]

Thanks for the input guys. I will definitely look into the new Yamaha. I would really like to put one on my boat for a test run before dropping 20 grand, but I'm sure the dealers aren't real big on that plan. Anyone out there have a 20' Champion Coastal series boat with a 200 or 225 Yamaha bolted on the back? I'll pay the fuel if you give me a test ride.

[Saltysacalait]

I heard from from a regional sales rep for a boat manufacture that the sho low water intake gets clogged really easy in shallow water and over heats.

[Saltysacalait]

Motors going to be great. Any way u go! Get hooked up w/ one of these prop stores and try the four blade props. Just put one on my boat. They are great on bay boats. If you were buying the mercury I would recommend u bolt on the bravo 1. New prop from merc.

[fun w son]

i swaped my tahatzu 90hp 2-stroke for a Yamaha 115hp 4-stroke and it performed the same as far as speed and hole shot. (hole shot actually improved)
i found the extra weight helped to conrtol the back end of the boat in high speed turns.

[Kajundave]

Originally Posted by flounder_smacker

If you can run a 20 inch shaft I would look in the Yamaha vmax sho. Not sure if you are looking for a new motor but the new yamahas are better than the two strokes.

X2 dat... The sho is about the same weight as your 200 or so I'm told . If you get a new outboard that is to heavy the boat will prefom poorly .
I know that Champion, skeeter,ranger all redesigned their pads to allow for the additional 4 stroke weight