more horsepower

How can I get more horsepower out of my mercruiser 200mr? I want to do engine mods first then Ill look at a new prop. any thoughts?

supercharger FTW....

a prop is still the easiest way to make your boat feel like it has more power.

(Message edited by twoten on June 26, 2007)

Port the heads and get a higher lift cam. Improve the intake air track. Supercharger or Turbocharger.
Just like a car.

There is alot of perceived power between props. If it were I, I would start with the prop. I'd expect you'll find you won't need to do engine mods after reproping.

Being this is Wakeworld, I'm assuming you're looking for better hole-shot performance. If that's not the case and you're going extreme and looking to increase the power by 30+ percent, then your probably right in proping it after the mods.

Can I go to a 4bbl carb?

that will help if you only have a 2...

Yes but it won't help much if you don't plan on internal changes. Basically, to get more horsepower you just have to get more air into the engine. Doing things to improve the air flow, like a bigger carb can help. You need to match each part or at least fix the worst air flow issues first. That's usually not the carb.
Displacement gives you more air in. Super and Turbo charging give more air in. Higher RPM gives more air in. Nitrous Oxide gives you more air in. Imroved air flow gives you more air in.

it may help. i don't think it will help much on hole shot. Have fun finding it, but I think a cam is prolly your best bet for better performance.

Dumping more gas in it may create horsepower, but I would look to change something else.

Bigger question: (assuming its the sea ray) How much are you willing to spend upgrading your current boat?

art, your too fast.

Usually I get a call in the middle of typing and I'm twenty minutes too slow.

easiest way to get more HP is to buy a new motor. I recomend getting a indmar or merc. rated @ about 350 HP or higher. you can get these motors customed wrapped in fiberglass, gell coat, with vinyl upholstery.

This is actually on my 21 ft four winns. It has a 305 v8. engine is the 200 mr....=200 hp.

So you can get up to 600 Hp with reliability if you want to spend a ton of money.
Standard way to pick up power is to put all the Marine parts on a longer stroke engine that's built from scratch with ported newer style heads and a marine performance camshaft. Change to a matched port injected intake and fuel injection system with multi coil ignition. Make sure the parts injection system and ignition are weather sealed. If you are willing to do that you can get just about any level of power you wish to run.
What you are starting with is not a great base for lots of power.
If you want to improve it some anyway you need a cam and a head porting job by someone with a flow bench.
Repowering with a new or rebuilt higher output motor might be a very good option because it could be done in a few days. I assume your 305 Mercruiser is a Chevy block so any small block would fit. That's up to about 400 cid or 6.5 litres

So Art what kind of money are we talking here? What If I want about 300 hp. I can get that with a 350 right?

300 Hp out of a 350 is not stressing anything. You'll find engine builders with kit built motors with that. You just have to make sure the engine rotation is the same and that basically comes down to the camshaft and ignition. Call some and see, and check the internet. You'll probably find that getting 350hp is not much more than 300 in price.
If you ask for one that can run regular fuel and has a really broad torque curve you'll get a great boat motor. Many will dyno the motors to give you exact specs and help break them in.
Much of the cost comes from things you add, like fuel injection and ignition. I'm in the Great White North so I'm not sure on the prices you can get something built for there.