Elux turbo injection

[glens]

Howdy all.

As some of you may rightly figure, I'm more of a Stihl fan than a Husky-liker.  Probably the main reason is that when I decided to graduate from the Homelites of my youth and only had X dollars to spend the (flash-in-the-pan) local Husky dealer wanted more for comparable saws than the local Stihl dealer did.  In small town shops that want to charge list price for everything, Huskies are more expensive than Stihls.  At least that's the way it seemed to me at the time.

Now that I've augmented my 036 with an 066 I find I'm using the 036 less and less, but that's not what I started this thread about.

Here I was, considering maybe getting a 372XP or so to broaden my horizons when the Dolmar 7900 gets the spotlight pointed at it, and frankly, I'm leaning more in that direction.  So it looks like I'll not be able to do something I wanted to try.  Maybe one or more of y'all will be so kind as to try it for me.

I'd really like to know what some resultant times are for a short series of cuts made back-to-back with one of the Huskies that has a filter cover which is separate from the top cover.  Particularly with that filter cover alternated being in place for one cut and removed for the next, then back on, etc.  It came to me yesterday that if the "air injection" actually gives short-term increase (works like a turbo-charger to improve performance by "injecting" air into the engine), that the saw should cut better with the cover on than off.  I'm guessing there will be no difference at best, and maybe it will actually run stronger with the mechanism bypassed.

The reason I'd like to see it done with one of the larger saws is so the the main top cover is able to be in place the whole time thus eliminating any variables <i>that</i> might induce.

I guess I was hoping for a comparison done with a stock saw, but I'll take what I can get.

Thanks a bunch.

Glen

 

[WRW]

Works like a turbo-charger? You mean it runs off the exhaust? Does it develop turbo lag in a two stroke? Got any pictures?

 

[SilverBlue]

Works like a turbocharger does not mean that it is a turbo. It does not provide any boost. in fact it would probably eat up more power.

 

[IOY1]

"in fact it would probably eat up more power"

Please enlighten us on this one!

I was also under the impression that any time there is a positive pressure, boost will be created. Maybe their Air Injection extracts the dust particles with some type of vacuum process.

 

[ricksvar]

Howdy Glens,

Well....one would have to assume air flow was not sufficient on the Huskys(which you may)and try this scenario to see if there is a improvement in performance with the filter cover off.I'am not going to try this one,VERY satisfied with the system on my 372.

In my opinion the positive air flow with the Huskys is complimented with the vacuum created by the carb with increased throddle.Like if I only pull a wagon up a hill or you get behind the wagon and help push,that would make it easier on both of us.

You might try this little test with your Stihls.They have to pull or drag(without positive air flow)air to the carb.It would be interesting to note if,with the filter cover off,there is a increase in cutting speed or a very slight increase in rpm at idle(probably need a tach to discern any difference).

Rick

 

[Joey P]

Originally posted by IOY1
"

I was also under the impression that any time there is a positive pressure, boost will be created.

Boost or postive pressure is only created when the engine can no longer take as much air as you are force feeding it. Don't forget now....Husky's and Jonsereds cannot get air anywhere except from what the flywheel is putting into the carb box, otherwise the whole clean air theory would be out the door. So in order for there to be boost generated the flywheel needs to be putting more air up to the carb box than the engine can handle.

I don't know if it does or not. I have never seen what kind of CFM the flywheel produces and I don't know exactly what kind of CFM the engine uses. But my best guess is that the Engeneers are Husky and Jonsered would not want a Forced induction situation to be happening. This would open a whole can of worms about engine life, fuel pressure, lean and rich operation at different levels of boost and different operating speeds.

I do have to say though that it would be cool as hell to have a turbo boosted chainsaw......hmmm....maybe in my spare time

 

[Tony Snyder]

1. What makes anyone think that the term "turbocharging" would have to be restrictive to exhaust driven pumps?

2. I would be inclined to think that the specially designed flywheel/fins/blower and shroud would offer some small amount of increase in air available at the carb, assuming that the the filter is clean.

3. I am ingnorant as to the affect of intake air boost on piston ported 2 strokes. Would it mess up the engineered flow dynamics? (Ben, you know anything about this?)

4. Wonder what fuel injection would do on 2 strokes?

 

[Joey P]

Originally posted by Tony Snyder


4. Wonder what fuel injection would do on 2 strokes?

Fuel Injection Exists.

Stihl has a fuel Injected chainsaw......it could be produced......but the market is not yet ready for such a price increase.....all in due time....all in due time.

 

[WRW]

1. Cause that's the definition of turbocharger.

 

[Jacob J.]

One time I cut my holding wood off and the tree went over backwards, taking the saw with it, and it smashed the air filter cover off my 371. I had to run it for the rest of the day without and there was a noticeable power loss. I tried tuning it a bit and that helped but not a lot.

 

[HUSKYMAN]

OK, I am somewhat familiar with turbocharging/supercharging as it is a hobby.

First, Husky's air injection is a supercharger, not a turbo since it is driven off the crankshaft and not the exhaust.

Second, Joey P, as long as the carburetor was large enough to supply enough fuel there would be no ill effects to positive boost pressure in the intake. The air is still being metered by the carb, and the proper mixture can be maintained. Only detonation in the cylinder would cause the life of the saw to be shortened, but this can happen in any saw that is not properly tuned and maintained.

Glens, your experiment is flawed because to get an accurate difference in power not only the cover would need to be removed, but the flywheel would have to be changed as well. The engine is still turning those big fins on the flywheel, and with the intake cover removed it gets none of the benefits of pressurized air entering the carb, but it still pays the penalty of having to move the air

 

[WRW]

Hard to call it a marketing ploy when that is not what the manufacturers claim. On the Jonsered site, they reference a Turbo Air Cleaning System...that is all. No turbo injection, no carburetion benefit, no injection benefit, nothing.
The Husky site calls it Air Injection with the same benefits listed as the Jonsered site... as well as the same omissions. They are not carburetion features, but they are filtration features.

The fancy name serves the same purpose as bright colored fishing lures...to catch the buyers eye.

By the way, I am in no way discounting the theory that higher pressures will move more air through a set sized orfice, but first one would have to know the cfm provided by the air cleaning system in question.

 

[bwalker]

Air injection is ment to keep the filter clean and doesnt provide any boost that I am aware of. If it did e lux would be the first to let you know.
In response to Tony's question about turbos on two strokes. They work fine once you tune all the gremlins out(Babcock had a turbo sled if I remember right). As far as fuel injection goes. TBI works fine in two strokes although you do not gain much in performance. DI on the other hand would make a two cycle saw use the same amount of fuel or less than a four stroke, have less emmisions than a four, and make more power to boot. Do a serch on the net for Aprillia ditech or piagio direct injection.The di tech motor is a 50 cc scooter powerplant that is built for the euro market. Very good emmisions, fuel consumtion, power and low weight.

 

[stihlfast]

Hey.... I took my slugish powerhead off and replaced it with a 500 hp V-8 engine that is supercharged !......anyone have any ideas how I can keep from setting my bar and chain on fire ?.......
(LOL).................

 

[glens]

<b>WRW:</b>&nbsp; "Got any pictures?"&nbsp; Yep, <a href="http://www.southwestfastener.com/images/powertools/husqvarna/airinjection.jpg"><img src="http://www.southwestfastener.com/images/powertools/husqvarna/airinjection.jpg"</img></a>.&nbsp; If I'd known of this image the other day I might not have needed to travel to visit a Husky dealer who let me see one with the starter cover off like in that shot (only it didn't have a carb and everything was filthy).

<b>SilverBlue:</b>&nbsp; "it would probably eat up more power."&nbsp; I was saying that in another thread the other day.&nbsp; It seems to me that if they were actually blowing into the airbox it would be blowing a bit of everything the fan blows.&nbsp; In order to prevent that, they must blow at least across the opening, possibly making the duct slightly negative before the carb even knows where to go for air itself.&nbsp; Refer to <a href="http://www.arboristsite.com/showthread.php?action=showpost&postid=102458">this AS post</a> and <a href="http://www.arboristsite.com/showthread.php?action=showpost&postid=102467">this AS post</a> in <a href="http://www.arboristsite.com/showthread.php?s=&threadid=10242&perpage=20&highlight=vacuum+filter&pagenumber=3">this AS thread</a>.

<b>IOY1:</b>&nbsp; Yes, boost equals any positive pressure in this situation so far as I'm concerned.&nbsp; If the process is in fact vacuum, well, that's pretty much what I've been conjecturing.

<b>ricksvar:</b>&nbsp; I'm not assuming the air flow is insufficient at all.&nbsp; I'm wondering which way produces the most power.&nbsp; Not to confuse in any way which would be the best to run in normal use.&nbsp; I'm merely proposing a test which should in no way harm the equipment beyond getting a little direct dust on the air filter.

<b>Jacob J.:</b>&nbsp; Did it return to normal operation upon merely installing a new air filter cover or was more entailed to get it back?

<b>Huskyman:</b>&nbsp; I would also describe it (if it's a pressurizer) as a supercharger.&nbsp; I'd used the term "turbo" since that's what Elux uses on the Jonsered line to sell it.&nbsp; Regarding the flaw in my experiment, I agree that it's flawed a mite in that the cover over the spark plug will not be in place, so the route the cooling air takes will be somewhat different.&nbsp; It shouldn't be a monumental change, though.&nbsp; Certainly not as influential as reconfiguring the air box situation might be.&nbsp; What do you say?&nbsp; Got a friend with a stopwatch?

<b>Brian:</b>&nbsp; The fins also sometimes serve to provide the force to actively position a throttle valve.

So, back to the question.&nbsp; Will anyone take a stopwatch out to the yard and check this for me?&nbsp; It's something I'd dearly like to know -- I get curious about stuff like that.

Glen

 

[Dennis]

OK...i will play here too...lol....

the definition of "turbo" as I recall is "forced air"...Elux is technically doing that...forcing air into the airbox...the main purpose of their "air injection" or in J terms "turbo" they are just marketing a cleaner filter...."marketing" being the key word. Don't think for a second that if Stihl (no I am not stihl bashing) didn't think of a way to use "Stihl Turbo" they wouldn't have...its all a marketing (there is that word again) game. And why wouldn't it be?

But realistically, the "turbo" or "air injection" keeps filters cleaner in my opinion. I have no doubts about it, I work on them all. And why wouldn't I?

 

[jokers]

Glens, get a life!
Jacob explained to you many of the reasons why Huskies runs so well. I don`t think anyone is seriously claiming that "Turbo" or "Air Injection" boosts engine performance in any direct way such as with a turbocharger or supercharger. I may have said myself that engine output is immediately enhanced by these features, but it is only to annoy guys like you. The manufacturers only claim that it helps keep your filter cleaner and that is in fact true.

The way I read your statements regarding a potential negative pressure at the inlet to the carb, I need to remind you that the fluid(in this case air) with the greater velocity is going to be the one doing the pulling and causing the vacuum. The piston in the cylinder is going to displace more air in one revolution than the flywheel, thus the velocity of air is going to be highest entering the engine. Furthermore, the carb throat provides the venturi, in the proper location, for increased scavenging of intake air on any saw. Where is the venturi that must be integral to Air injetion in order for it to cause a negative pressure at the carb throat? Right, there isn`t one. Accept that Turbo and Air injection are a better prefilter air cleaning method than most of the competition have and move on with life.

Russ

 

[Newfie]

Such a fuss for a guy who had to be off the topic of his own thread for the first three paragraphs before actually getting around to his point, which he obviously missed.

 

[glens]

Okay everyone, settle down a little.&nbsp; I <i>accept</i> that the feature serves to keep the filter cleaner longer.&nbsp; I don't have to run one to see how that would be so.&nbsp; I even think it's a good idea.&nbsp; The thing I want to know is what to really think of the statements one occasionally encounters that it also increases performance.

I haven't missed a thing yet, newfie, and how the hell can one be off-topic while setting up their own post?

Russ, all those other factors Jacob mentioned are thoroughly understood on my end, are totally immaterial to what I want to determine, and only serve here to cause confusion.&nbsp; A venturi is a device which necks down fluid flow in order to increase it's speed, thus decrease it's pressure (which in the case of a carburetor serves to draw the fuel into the stream).&nbsp; [We used some killer venturis that ran off service air (and were loud as hell) which sat on top of 55-gallon drums to make super vacuum cleaners at some of the power plants I worked.]&nbsp; If you put a vacuum on one end of a duct and put a greater one on the other end, the greater one will win, obviously, but the greater one will have lesser net effect than it would have.&nbsp; I'm thinking the way the air flows in relation to the fan-end of the duct that there's possibly a slight vacuum generated in the duct in general (and I'm envisioning something on the order of maybe a full-single-digit percentile, at most).&nbsp; Obviously, the greater vacuum created by the upward-moving piston will prevail.&nbsp; Look, why don't you be a stand-up guy and spend five minutes with a stopwatch and a friend so I don't have to spend six hundred bucks plus make a friend in order to find out what I'd like to know.

It can't be much of either vacuum or pressurization that are produced else the jetting would be off when the winter warm-air flap is opened (and the filter gets every bit as dirty as Stihl, et al.). This is something that I'm merely curious about -- it's not a cause for loss of sleep.

Thanks.

Glen

 

[bwalker]

I just looked at a 372 and it appears to me that the airbox would not be pressurized at all. The sytem works by basicaly using centrifugal force to expell debris to the outside of the flywheel. The airbox then draws its air from the zone toward the center of the fan which has less debris floating around in it. Kind of shoots a hole in Walt's theory that AI drives particles into the filter.
I still wonder if it doesnt do as good a job as people think in that it still allows fine particle which are the ones that clog filters to enter the filter area. A filter may appear cleaner in this scenario, but in reality could be quit dirty.