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joseph m. hahnl
06-19-2010, 05:38 PM
Same displacement. Where does the extra 20 hrse come from?
The Lower Unit? The power head? The Ignition? all of the above?

http://www.evinrude.com/en-US/Engines/ETEC_INLINES/ETEC_40_INLINE (http://www.evinrude.com/en-US/Engines/ETEC_INLINES/ETEC_40_INLINE)
http://www.evinrude.com/en-US/Engines/ETEC_INLINES/ETEC_60_INLINE

(http://www.donzi.net/en-US/Engines/ETEC_INLINES/ETEC_40_INLINE)

gcarter
06-19-2010, 05:40 PM
Links don't work

gcarter
06-20-2010, 11:07 AM
I don't know, but I'll take a stab at it.
It could be nothing more than trying to have a product to compete w/Merc, etc. So by detuning, smaller injectors, you have a 40 HP engine
to plug into that market niche.

mrfixxall
06-21-2010, 09:39 PM
the etec 40 is a 3 cylinder engine and the etec 60 is a 4 cylinder engine..

MOP
06-22-2010, 06:38 AM
Years back the only difference between a commercial 50 and a pleasure 60 was the carb and its intake opening and the tuned exhaust. Like you said both share the same block and cubic inches, one is given more breath as I like to call it more in and more out. Long before these late model 300's you could easily get over 400 out of a 235 John/Rude block, I have seen several with "9" carbs three YES 9 carbs! Dellorto one barrel carbs were a Unisync pain but when right made great HP, one on each by pass cover with a reed block and the normal three two barrels on the intake.

joseph m. hahnl
06-24-2010, 07:51 PM
the etec 40 is a 3 cylinder engine and the etec 60 is a 4 cylinder engine..
NO they are all twins 40 hp,50 hp, and 60 hp. They are identical displacement

Engine type Inline 2-Cylinder E-TEC DI
Displacement 52.7 cu in/864 cc
Bore x Stroke 3.601 x 2.588 in / 91 x 66 mm

So Phil your saying it's carburation and porting?

handfulz28
06-24-2010, 10:37 PM
It's very common to take a given displacement and "choke" it with smaller carb-throttlebody bores/jets/injectors to reduce the power.

My personal example: Suzuki 400cc 4-stroke dirtbike. The street model came equipped with a Mikuni 36mm carb, the off-road model came with a Keihin 38. No change whatsoever accept the carb, entirely different bike.

Think about how many people have done "carb & intake" swaps for an increase in power.

Nowadays on modern two-strokes, probably the most important difference is in the ECU; perhaps a throttle body bore and maaaybe a different injector.

gcarter
06-25-2010, 06:53 AM
It clearly says these are fuel injected engines, not carbed.
It's a simple matter to use an injector with lower delivery and
different programming.

Just like I said above.

lars
06-25-2010, 07:16 AM
George is absolutely right.
To get more specific I know that the 40HP, 50HP and 60hp are the same engines except for the EMM "brain" of the engines. That gives the 50HP a bit more effect than the 40hp. The 60HP is the same as its brothers in the powerhead, but has also different software. It has however on top of that a water valve in the exhaust that offers significantly better mid range than the other two. The differens between the 40hp and the 50hp is not worth the few extra $$, but if the boat could handle a little more power the 60hp is 15-20% more effective than the 50hp and that's worth every extra penny in my opinion.

joseph m. hahnl
06-26-2010, 09:15 PM
It clearly says these are fuel injected engines, not carbed.
It's a simple matter to use an injector with lower delivery and
different programming.

Just like I said above.

yes true the E techs are direct injected . But through the years OMC twin 40hp & 50 HP engines have allways been the same displacment.

The E tech does not have intake ports so atomization would be done through an injector yes.

I thought because the Hp is measured at the prop and not the power head. That it could be gearing in the lower unit which could deliver more torque.

As outboards have allways been more timing advance than throttle.
It would seem that ignition would have an effect also.