Elux turbo injection

[glens]

Yeah, the box is evidently pressurized by my reckoning as well, Frank.  Unless somehow there came to be an altered relationship between the venturi and metering diaphragm, that is.  Is Elux venting them to the inside of the air filter yet, or is it still just to the airbox?

It will be interesting to get some cut times reported on this issue.  Hooking a gauge up would be interesting too, but how would one decide where to sample?

Something I find puzzling is the image this gives me of a centrifugal fan moving enough air to both cool the engine spinning it <i>and</i> to stuff some into the engine intake.&nbsp; Seems like even if it could do so at idle, that under load at high RPM it wouldn't be able to keep up with the demand.

We'll get to the bottom of this... unless Elux hits us with a cease-and-desist order under the DMCA or whatever new law it was that prohibits reverse-engineering.

Glen

 

[glens]

What the hell's your problem?&nbsp; Seriously, Brian, I'm a little concerned.&nbsp; Maybe you should seek help.

Glen

 

[Crofter]

Is it sucking or blowing?

Had a fuel line prob with the 365 and decided to do a little experiment while I had it apart. The air supply to the filter compartment is tapped off the INSIDE of a curved path to the cylinder fins. Centrifugal force sends heavier than air particles to the outside of the stream and on past the cylinder head. Thus ejected particles are not forced into the air box.

I drilled a 1/8 hole in the centre of the filter cover and attached one end of a water column manometer to it. There is a positive pressure, but not very much. At idle it is barely measurable but increases to 3/8 of an inch at full throttle. Considering that one atmosphere is close to 360 inches water column, this is not much pressure to potentially influence performance but it does prevent any air except what has been throu the centrifuge from getting into the filter compartment.

Frank

 

[Lumberjack]

Air injection

From what I understand they whole air injection thing isn't very new. All it does is use citrifical force to sling the heavy particles out of the incoming air before it gets to a the air filter. It is very similar to the air intake on a tractor, except the engine makes the air sling not negative pressure in the air intake. The only power gain I could see is that the air cleaner would stay cleaner longer so there would be less restriction. The whole thing is based on removing dust from the air before it hits the air filter.


Carl

 

[earache]

glens, great question.
stihltech, good point. I work on turbo-charged diesels all day every day, and yes, it is a sealed system. If there is a leak, and there is a specification how much the system can leak without affecting performance, the engine will not build enough boost, and therefore overfuel, losing power. What husky has is not a turbocharger. The air is forced through the airbox and over the filter. The carb only takes what it needs. The airbox is not pressurized since it is not sealed, it merely blows air over the filter. Yes it does work. My dad and I ran a few comparisons between the husky saws and older jonsereds and a couple stihls. The filters on the huskys were always cleaner.
Cant remember who asked about the two stroke and turbos, yes it does work. Quite well actually. Detroit Diesel did it for years. They made many, but the most impressive was the 8V92TA. It was a V8, 92 cubic inches per cylinder, turbo charged, after cooled, and it had a supercharger. It was a two-stroke. Had 455 horse, and back then, that was alot. Never heard a smoother sounding diesel. Dont see them anymore.
Glens I will try and run that test for you. I have a 372.

 

[Crofter]

Earache; I am just quibbling about technicalitys here since this is mostly what this subject is about.

Originally posted by earache
. The air is forced through the airbox and over the filter. The carb only takes what it needs. The airbox is not pressurized since it is not sealed, it merely blows air over the filter.

The air box is pretty much sealed and yes the flywheel fan does keep it slightly pressurised. (3/8 of an inch W.C. is pretty insignificant in any possible performanc boost though)




Cant remember who asked about the two stroke and turbos, yes it does work. Quite well actually. Detroit Diesel did it for years.



Since the Detroit diesels are not base compression engines though as in a saw it might not be a good comparison. Vacuum created by piston does nothing toward induction in the Detroit. They depend on a positive displacement lobe type, crankshaft driven supercharger to force in air and drive out exhaust. They can be and some are additionally turbocharged with an exhaust driven turbocharger.
Traditionally, crankshaft driven positive displacement intake pressurisers were called superchargers, and exhaust driven ones (which happened to be turbines ) were called turbochargers. The terms are not mutually exclusive.



Glens I will try and run that test for you. I have a 372.

It would be interesting to see some timed cuts with cover on and off.

Frank

 

[Lumberjack]

Why not make a small dyno and test it with that. That would be more accurate than timed cuts. I know that an ICE operates like an air pump. The less restriction in the intake and exhaust the more power it makes. I disagree with the notion of running an engine without any filter, exspecially in our line of work when there is constantly huge amounts of dust in the air.


Carl

 

[stihltech]

turbo

Isn't one of the saw builders set up with a dyno?

 

[WRW]

Frank,
Correct me if I'm wrong, I have been before and expect to be again. Isn't the turbocharger a supercharger but the supercharger not necessarily a turbocharger?

earache,
The question was, in effect, if it is a turbo on a two cycle (chainsaw) will it have a turbo lag. I know those diesels do!

 

[glens]

Thanks, Franks.

Being not familiar with the appearance/layout of the filter element on the 365 I wonder if it's possible the sample point was being subjected to and influenced by the positive (reverse) pulses that are (invariably?) present in the "piston-ported" intake design.

Let's go with it as being provided by the fan/ductwork, though.&nbsp; My HP48 converts 1_atm to 407.2_inH2O, so the amount is even more miniscule than already described, but Frank is using a Canadian measuring device and there's no telling what kind of Imperial Inch or whatever's being used (hahaha).

I'm not considering running the saw without any filtration, Carl, but for testing purposes only, to do so without the airbox cover (leaving the filter element in place).

There are some folks who run their saws without any filters, for several seconds at a time.&nbsp; Wouldn't it be a hoot if the fan-side of the ductwork could be turned around enough that the fan blows directly into it and, though more dirt would reach the filter, there might be some tangible benefit to the working end of the saw?

I eagerly await your results, earache!

Glen

 

[Crofter]

WRW ; You are correct, supercharged means intake pressurised above atmospheric pressure by whatever means. Exhaust turbocharging being only one of them. Traditionally though, at least in aircraft engines, the term " supercharger was applied only to devices that were positive drive from the crankshaft.

Glens: I believe I was measuring mean not peak pressures. The pressure was a pretty smooth curve in relation to engine rpm but did start to drop off slightly and be a bit erratic as the engine started to break into four stroking which I have it set to do at max rpm.

I said thas 3/8 of an inch water column pressure was pretty inconsequential in relation to tne atmospheric pressure which was approximately 360 inches of water column. Roughly 1/1000
You inform us that indeed a standard water column at sea level is 407.2 inches. I am at 609 feet above sea level here. I forgot to say that I had corrected for local conditions. LOL!


Frank

 

[WRW]

Frank,
Does it make any difference that the piston induced vacuum/pressure cycle creates only .5 bar? The 3/8" water column would only be 1/500th of that...at your altitude.

 

[Crofter]

WRW: I don't think that that small positive pressure created in the filter compartment by the fan has measurable boost to the engine. We are kicking around something pretty small here. I believe Jacob J felt that his saw ran weaker and possibly richer withe the cover off. That would have removed any possible boost but could throw in the additional variable of the engine then being fed cooler air. (with more density but different fuel vaporisation ability)
This is fun, but only a game and it pisses Rocky J Squirrell off to no end: such hypothetical foolishness! We know the system works tho to help filter maintenance and since a turbine is used to create the force that aids the separation of the particles, I guess Elux is entitled to use the nickname " Turbo " injection which some people associate with being turbocharged. They might be a bit sly with their naming of it but at the most you could call that naughty! I think Glens is secretly on Stihls payroll and is trying rather desperately to discredit Elux. I believe he owns only Stihl saws. I own one of each so am to be considered to be either absolutely unbiased or unable to make up my mind, whichever you prefer.

Frank
P. A. E.

 

[glens]

Frank, I wish sometimes I were on a payroll somewhere (as opposed to being self-unemployed), but it's hard to imagine finding a boss as easy-going on myself as I am, hahaha.

I'd figure a turbine to be essentially a fan upon which a flow of gas impinges (usually in conjunction with interleaved stationary blades) to produce rotary motion of a shaft.&nbsp; While in this case the fan is driven by gas, it's indirectly so and is thus really the (secondary) driven member.&nbsp; What we're talking about is a piston-driven fan and not a turbine-driven piston, so the term "Turbo" is really an incorrect and misleading choice here.&nbsp; I'd be more inclined to describe it as "Super".

What I had in mind about the reverse pulses maybe affecting the instrument had to do with the possibility that the very short duration (but with high acceleration) pulse might register a positive on the meter which the longer-duration but much weaker negative element would somewhat counter, but maybe not soon enough to give a good general average reading.&nbsp; By the way, I'll go in on a filter cover with you to replace that one; just let me know (privately) where to send how much.

If indeed the (miniscule) positive pressure measured is a result of the fan/ductwork it would most certainly assist the filling of the crankcase beyond just the piston "sucking" it in.&nbsp; I don't discount the possibility in the least that's what's going on, and Jacob's stated impressions would lead one to believe that is so as well.

It will be fun to hear of the cut times.

I might just go pick up a junked-out saw this winter and drive the crank externally as I described earlier.&nbsp; (Wasn't that a hoot to describe going through all that fancy work and then using a smoldering stick as the measuring device?&nbsp; I'd thought sure that someone would comment on that.)

I don't own <i>only</i> Stihls, but I don't own any Eluxs (yet).

Glen

 

[Crofter]

Glens; you are right in saying a turbine is a driven element, not driving where it becomes a pump or compressor, so if it is indeed pressurising the intake (which you seem bound to dispell with magical one way transfers of energy without movement of material), it is supercharging. The nickname "Turbo" is however vague enough to relate to "turbulent" so I doubt you will be able to get a cease and desist order against Elux!.

Dont worry about the little hole. I got a rubber plug for it that looks original. Anyway those high acceleration pulses will keep any dirt out.

Frank
P.A. E.

 

[glens]

Frank, I imagine that if you were to remove both the cover and the filter before firing up the (piston-ported) saw, you'd see a little cloud in the throat of the carburetor at idle, and it would expand to perhaps something the size of a ping-pong ball just outside the throat at higher revs.&nbsp; If you were sampling an area which was in or very near the "cloud" we might not be yet so close to the bottom of this as we think.&nbsp;

When I debug stuff I try to hit it from every side just to be sure, and I guess that makes me appear to be a nay-sayer or a devil's advocate at times.&nbsp; Believe me when I say this is merely a curiosity on my part and that I don't <i>want</i> it to be one way or the other; rather, simply to know.

Glen

 

[earache]

This may be the best thread I have read yet. Thanks fellas, keep it up.
Above statements are in no way derogatory.

 

[jokers]

earache, this isn`t meant to be a shot at you or anything but all I can say in regard to your last statement is different strokes for different folks.

This thread has turned into something like watching a loved one die from a slow cancer or something I would expect to see on the off topic forum, a political exchange where mquinn and oakwilt endlessly trash talk the current head politicians and the "idiots" in the US who support them.

I recognize that Glen has above average intelligence in some areas but he seems to be making a career of persuing the "Turbo" issue and it`s alledged contribution to engine performance. So far, the only person whom I recall tying "Turbo" or "Air Injection" to engine performance in any way that wasn`t tongue in cheek is Glen, with JJ offering a minor observation and no follow up. The whole thread is becoming contrived in my opinion, but hey, everybody gets equal time to hash out what`s on their minds so it`s none of my business I suppose.

In that light, I say to Glen and whomever else that wants to continue the thread, carry on.

My opinion of Turbo/Air Injection is this, I currently have and run 7 Stihls and 6 Huskys and the Husky air filters stay cleaner by a long shot. Not nearly as much bug dust on the Husky filters either. The scientists here can put forth all of the conjecture and armchair application of physics that they want, but what I see in the field is cleaner air filters. I also know that on some of the Huskies I tune the carbs with the filter covers off because the screws are such a PITA to get at and it makes no difference to saw performance in the cut with the cover reinstalled. I`ve tried the saws both ways to be sure.

If anyone here has a bone to pick with Elux because of an implied engine performance benefit other than what you get from a clean air filter, so be it, but I believe the fact of the matter is that if there were a real and measurable benefit, Elux would be shoving the data down our throats.

Russ

 

[Crofter]

What Makes I Tick?

I pretty much agree with Jokers take on the whys of Elux's filtration system esp. since I sampled the pressure in the filter box. The sample point was at least 2.5 inches away from intake of carb. and also out of line with air stream from fan housing. Glen that is a valid point about local disturbances at the sampling point possibly being an influence in some things.

If you are not careful about your observations, you can come to the conclusion that it is the waving of the tree branches that causes the wind to blow. It amuses me when people are too quick to accept what they think they know. I always was captivated by the need to know WHY something is so; not merely to accept that it is. Even so, I still have to readjust my thinking when the clarity of hindsight comes.

Jokers, I seem to remember some instances when you were into convoluted discussions verging on quibbling too; I think it is good, since every once in a while a little point of understanding comes that you can apply at a later time to something else. I guess this is more philosophy than what makes a chainsaw work so perhaps we should be banished LoL!

Frank

P.A.E.

 

[jokers]

Quibbling

Hi Frank
I`ve been in more than my rightful share of disagreements that amount to nothing more than quibbling. I agree that sometimes it is beneficial and enlightening and I am sorry if I came across as condemning this current discourse. I was simply trying to state my general lack of interest in the detail that this thread contains although I admit that I have kept abreast of the discussion.

As far as banishment is concerned, the other place that I assume to which you are referring has become laughable in what they allow for some, but not for others.

I have been banned again and I`m not worried because the truly meaningful discussions that I`m after are normally occurring here and not there. This is due in no small part to the skillful and minimal moderation that Darin and Dennis excercise.

I think that Dennis and Darin recognize that human interaction will sometimes vary and will ultimately tend to moderate itself to the standards of the group or civilization. When you have a heavy handed moderator who panders to the weak and social misfits known as liars or complete idiots who will not be swayed by fact or reality, such as the other forum has, the rest of the people will lose interest. That`s Ok though because I know that I have AS to come to and could even start another board if AS changed it`s format too much. Maybe that style of business at the other forum is in their business plan.

As always Frank, good to share thoughts with you.

Russ