Now with STIHL exclusive IEM System

[jhellwig]

http://www.stihlusa.com/chainsaws/MS280.html


Intelligent Engine Management

Deer god what has the epa made them do now?

 

[Lakeside53]

Yep... I haven't seen it in action, but have been told it works real well.... I wrote up something on it in other posts in December. Expect to see it on more saws later.

Now your saw has a brain... by by modding of this one...

 

[Peacock]

So this is different than the compensating carb?

 

[jhellwig]

I suppose scince they have efi on snowmobiles now that don't use a battery or an o2 sensor(that I know of or have seen on one) it was just a matter of time.

 

[Lakeside53]

So this is different than the compensating carb?

Yes...

Here's an extract of what i wrote previously:
It's moving that way though... a new fuel/ignition system that Stihl is in the process of bringing out January 2007 (first on the MS280) has a microprocessor in the coil and connected to a solenoid in the carb. A separate set of magnets on the flywheel generates power for the processor and solenoid operations (which is why you need the EDT8 tach). The microprocessor reads rpm, and in addition to adjusting timing, also adjusts the mixture 30 times per second for "optimal" mix (power verses the epa) in a wide range of conditions. In other words, it adjusts while you are cutting... It does this by making minute adjustments and watching the resulting rpm increase or decrease. Tricky stuff... and guess what? No H screw... and good luck in messing with the carb and ignition timing.


A simple analogy of what is happening is the height of the metering needle arm is being adjusted to suit different conditions.

 

[Peacock]

Thanks.

Sounds like we are repeating the late '70's and early '80s from the automotive world. Maybe not a good thing.

But look where we are now. 400hp and 30mpg!:biggrinbounce2:

 

[jhellwig]

Yes...

Here's an extract of what i wrote previously:
It's moving that way though... a new fuel/ignition system that Stihl is in the process of bringing out January 2007 (first on the MS280) has a microprocessor in the coil and connected to a solenoid in the carb. A separate set of magnets on the flywheel generates power for the processor and solenoid operations (which is why you need the EDT8 tach). The microprocessor reads rpm, and in addition to adjusting timing, also adjusts the mixture 30 times per second for "optimal" mix (power verses the epa) in a wide range of conditions. In other words, it adjusts while you are cutting... It does this by making minute adjustments and watching the resulting rpm increase or decrease. Tricky stuff... and guess what? No H screw... and good luck in messing with the carb and ignition timing.


A simple analogy of what is happening is the height of the metering needle arm is being adjusted to suit different conditions.

I remember reading that now that you post it.

 

[PES+]

And that ties in with the Walbro SEM Mexico thread

Walbro and SEM are working together and Stihl bought the exclusive on a system...or at least a name....I doubt the reliablity will be there as digital SMD (surface mount device) does not at all care for chainsaw enviroment.....we shall see

 

[PES+]

SEM is an Opcon company
Walbro is a TI Automotive company

Multi nationals run riot

 

[precaud]

I doubt the reliablity will be there as digital SMD (surface mount device) does not at all care for chainsaw enviroment.....we shall see

What about it? Despite my early skepticism, SMD has done well in automotive applications.

 

[PES+]

Give me your address and I'll send you a freight car full of bad Ford Triton coils

 

[Lakeside53]

Walbro and SEM are working together and Stihl bought the exclusive on a system...or at least a name....I doubt the reliablity will be there as digital SMD (surface mount device) does not at all care for chainsaw enviroment.....we shall see

All Stihl coils have had SMD for about 6 years... The failures (few and far between) were caused by component failure (a single diode in almost all cases), not the mounting methodology.

 

[PES+]

When it hits -30 out there let me know Lake......

 

[precaud]

When it hits -30 out there let me know Lake......

You're throwing out generalizations. Be specific; what happens at -30?

 

[Lakeside53]

It's -30 somewhere right now...

If it's designed right, it's never an issue... Cut corners, it is.. Like a few other on AS, I was hardware engineer, designing this stuff for a long time...

 

[manual]

Give me your address and I'll send you a freight car full of bad Ford Triton coils

I'd settle for one good one right now.

 

[PES+]

NAPA has them....and theirs WORK.....check your local or use NAPA online