De-tuning a Looper ?

[22ISLANDER]

What is the difference between a 225 Looper and a 200 Looper ?

Is it just the carbs ?

Can I put carbs off a 200 onto my 225 without hurting the engine ?

I'll sacrifice some horsepower for a little better fuel economy...if it will work.

Both engines are the same year (87), and I know the 225 has a bigger bore carb, just wondering if i can get away with it.

 

[jimmbo]

Re: De-tuning a Looper ?

Before you go and mess around with your engine have you maximized your rigs economy otherwise? Proper proping? Deep sixing unnecessary cargo on the boat? Proper loading and trimming? Just running at speeds less than WOT?
Putting smaller carbs will reduce the top end breathing which then makes it more difficult to choose the proper prop. That could hurt the engine.
I am assuming the two engines have the same displacement. That doesn't mean they have the same block, port timings could be different. Since the 225 has larger carb venturies it means the 225 needs more air to make the extra 25hp. More air in means more exhaust out, hence different porting and exhaust tuning, and potentially carb calibration.

 

[22ISLANDER]

Re: De-tuning a Looper ?

Thanks for the reply Jimmbo.

From what I have been told, the only difference is the carbs.

The prop on the 200 is the same pitch as the one on the 225. ( which is the suggested prop for the boat).

The only thing I carry in the boat is what I need for offshore fishing, and I unload it after every trip.

A typical trip is 60 miles, and you can't very often run WOT due to sea conditions..1.5 miles per gallon is average, trolling or cruising.

Boat is a Wellcraft 228 Sportsman WAC, and most I've seen are running 200's, some even with 150's. I think the original engine on the boat was a 200, because it is mounted on a Seadrive, and I've been told by many folks that it's the first seadrive they have seen with a 225.

How's things in Edmonton ?

( Alberta born 'n raised )

 

[kenmyfam]

Re: De-tuning a Looper ?

Is there such a huge difference between the 200 and 225 ???? in fuel consumption ???? Do you feel you dont need the entire 225hp ???
Rough guess would be 2 GPH ish at WOT and significantly less at lower RPM.
Just my thoughts to ponder.

 

[22ISLANDER]

Re: De-tuning a Looper ?

Well I've been reading as much as I can find about the differences, and I dont think going down to 200hp is going to make much difference when it comes to performance, maybe a little slower out of the hole, and not as fast on the top end.

The 225 is notorious for fuel consumption on a larger boat, and the 200 is actually recommended.

Here is a website I've been reading about the carb differences.

www.2strokeonly.com

 

[kenmyfam]

Re: De-tuning a Looper ?

Well, there is without doubt no harm in trying it. Just make sure you keep the original carbs just in case you choose to go back.
Good Luck and keep us all posted.