Dynamic Cylinder Deactivation

[t vago]

Originally Posted by Heihetech

the 500 C temperature rise? much higher than 100 C coolant temp, high enough for heat to escape to coolant. When heat comes back during next expansion, heat source temp is only 100 C. So the loss always larger than the gain and such loss must have been doubled due to TCD'S action. The double loss will also be enlarged by all 50% of the cylinders! not only one or two. Saying negligible isn't correct.

What is the thermal conductivity of the metal that forms the combustion chamber? How long would it take to transfer the heat energy from the adiabatically compressed air to the metal combustion chamber walls? How long would that take to have that exact same heat energy transfer from the metal combustion chamber walls to the coolant? If we went by your laws of thermodynamics, instead of the real laws, car engines would heat up in less than a second after being turned on. Therefore, it's obvious that more things are in play than are dreamt of in your universe. Also, heat loss from adiabatic compression or expansion is indeed negligible with respect to running internal combustion engines.

You really should not speak about things of which you don't know. You come off looking like an ignorant snake-oil salesman.

Originally Posted by Heihetech

There seems a Mr. TCD who keeps saying that DCD is not as good as TCD. But his knowledge seems coming from thermodynamics only, not from control
electronics. Moderm engine is controlled by ECU, by oxygen sensor, by closed loop. DCD needs even more controls, by DCD controller, by WBO2 sensor, by high-lambda loop, by multiple lambda set points. If you don't know all of the basic knowledges, your comment on DCD could become unreasonable. I won't teach you everything related to DCD. You may wish go to read some textbooks before making qualified speach.

If you can get a WBO2 sensor that is capable of significantly greater than 1.5 lambda, then I could at least think about your claims. However, as production WBO2 sensors do not go that high, I have to view your claim with no small amount of skepticism.

Originally Posted by Heihetech

I'm talking about the benefits of DCD because I invented DCD, I did my contribution to this world. What about you, Mr. TCD? Did you join the actions
in 1970s and 1980s in TCD invention? Or you had made any TCD controller by which TCD aftermarket retrofitting can be implemented. How many TCD engines have you implemented or retrofitted? Show all of us your qualification.

Appeals to authority, such as this pathetic paragraph above, are typically used by people who have a weak argument to begin with. I could claim any number of things on the internet, but unless they're backed up by real-world results that others can repeat, the claims are worth nothing.

I'll put my own knowledge up against this gadget of yours any day, Heihetech. I don't need some fabricated award claim from a non-SAE sanctioned contest to do it, either. The internal combustion engine is inherently a thermodyamic beast, which is something you can't seem to fathom. In order to intelligently discuss any form of fuel savings from modifying the basic operation of a thermodynamic engine such as the internal combustion engine we're all familiar with, it's necessary to resort to thermodynamics. Otherwise, you will (and did) forget something crucial.

Here's a question for you, genius. Name all of the forms (not manufacturer trade names) of variable displacement that exist for the internal combustion engine.

Originally Posted by Heihetech

The fact is driver always needs more power than the engine can provide with half its cylinders shut off, so TCD could be ALWAYS OFF. ONLY ON AND OFF!

Thank you for proving my point for me.

At part-throttle cruise, the full engine output is not needed, so it's desirable to have the ability to shut off some of the cylinders.

Originally Posted by Heihetech

Why "Forget about O2 sensor feedback"? I told many times that DCD's fuel saving secrute is by WBO2 Sensor, which determines the target of high-
lambda control. You may know what is high lambda? It should be much higher
than the unity. Then you may figure out how much fuel would be injected vs
air intaken? You was wrong to expect more fuel injected.

So you propose to completely eliminate the stock engine computer, then. That's really easy to do - much easier than fitting variable displacement onto an existing internal combustion engine...

Or was there some other way you were going to fool the stock engine computer from seeing some cylinders misfiring?

Originally Posted by Heihetech

Misfiring? That's a trouble to most conventional engines that needs to be avoid. But to DCD controlled engines, "misfiring" is what we wanted, it's
the sign of DCD in progress, but don't have real physical misfiring. If you
are afried to see "check engine" light on, I can put it off by program.

No, I am not "afried" of anything of the sort. What I am afraid of seeing people either giving you money for a scam, or destroying their engine as a result of installing your scam.

Engine misfiring is never good. You may claim otherwise, but it's never a good thing to have completely unburnt fuel-air mix exit the combustion chamber. At best, you're just wasting fuel, and at worst, you're burning up your catalytic converter AND prematurely wearing out your piston rings due to fuel dilution of the engine oil clinging to the sides of the cylinder walls.

How do you propose to prevent engine misfiring with your gadget? You do realize that an AFR of 17:1 (1.15 lamda) is about the limit at which a perfectly stock ignition system will reliably fire off, without any modifications. Beyond that, and you're starting into cat damaging territory.

And how again do you propose to eliminate excessive NOx and unburnt hydrocarbon emissions with this DCD gadget?

Originally Posted by Heihetech

"check engine" light on and OBD-II codes are enough to present
the trouble. Why make more trouble by limp-in mode? In fact, for many
times I demo my DCD controlled vehicle to passangers, they even don't
know DCD CONTROLL has been changed from off to on to max in multiple
stages, engine still runs smooth under DCD control.

Closest thing I can think of that matches your gadget's description is an hideously overcomplicated form of EFIE with wide band O2 feedback. If that's the case, I can do the same thing (which is to burn less fuel compared to stock) that your gadget does, with a few comparators and a WBO2 gauge controller.

Originally Posted by Heihetech

Dear Mr. TCD,

To fight bcak your chanllenge from TCD, I'd like to chanllenge your TCD by DCD with some real physical actions -----

Let's find 2 vehicles with identical make and mode, then you make your TCD retrofitting, I make my DCD retrofitting, then test driving under the same conditions, as to see who saves more fuel, thus who beat who.

Next, let's do cross retrofitting ----- I retrofit your TCD controlled vehicle
with DCD; and you retrofit my DCD controlled vehicle with TCD, as to see
who gets higher additional fuel savings beyond the previous retrofitting.

Although you are the winner of thermodynamics, you may not become the
winner of fuel saving technology.

Bring it, Heihetech. You've been peddling this snake oil device of yours for at least two years to anyone who might listen, with no measurable dent in the market. I can begin to see why.

Originally Posted by Heihetech

How do you know "limp-in mode by cutting fuel to 1/2 the available cylinders"? You designed something like this? or you have got used to turn 50% cylinders off by TCD that makes vehicle into limp-in mode ?

I know modern engine control theory, which is something you obviously have no clue of.

Look up OBDII codes P0300 through P0307, and tell me how they are generated.

Originally Posted by Heihetech

I NEVER SAY "a true variable displacement system somehow uses more energy to work than your DCD". That's your original statement. What I said
is TCD will save less fuel than what DCD could save, and part of TCD's fuel
savings will be lost due to certain reason. The smaller saving is still a positive
number, not a nagative number as you argued.

Your own chart stated that traditional cylinder deactivation incorrectly had a negative contribution to engine efficiency. Negative contribution means work put into the system. Don't put words in my mouth, and learn about how an engine works.

Originally Posted by Heihetech

true variable displacement system? Please don't forget DCD controlled engine is a better true variable displacement system than TCD controlled engine.

Where are you selling these things? eBay? Summit Racing? JEGS? JC Whitney? Amazon.com? Where?

Are those CRICKETS I'm hearing?

Originally Posted by Heihetech

passing emission testing problem? Just switch DCD off, everything will go back to the original. Then no more passing emission testing problem.

Unless you pass one of them mobile emissions checking trailers. Or until your cat burns out from excess unburnt fuel. Or until your engine starts burning oil from worn-out piston rings due to fuel-diluted oil.

Originally Posted by Heihetech

turning off fuel delivery to 1/2 the cylinders in an engine? VERY BAD IDEA ONCE DCD HAS INVENTED. DCD has integrated such function, but DCD
seems never have a need to go to that dead point. The smart guys will
try advenced DCD BEFORE going to try your entery-level skill.

Of course, this is why all of the major car manufacturers implemented "DCD" such a long time ago.

Oh, wait! They didn't, did they? There must be a reason (not involving nefarious conspiracies partnering with "Big Oil")...

[Heihetech]

Originally Posted by t vago

Engine misfiring is never good. You may claim otherwise, but it's never a good thing to have completely unburnt fuel-air mix exit the combustion chamber. At best, you're just wasting fuel, and at worst, you're burning up your catalytic converter AND prematurely wearing out your piston rings due to fuel dilution of the engine oil clinging to the sides of the cylinder walls.

How do you propose to prevent engine misfiring with your gadget? You do realize that an AFR of 17:1 (1.15 lamda) is about the limit at which a perfectly stock ignition system will reliably fire off, without any modifications. Beyond that, and you're starting into cat damaging territory.

And how again do you propose to eliminate excessive NOx and unburnt hydrocarbon emissions with this DCD gadget?

Closest thing I can think of that matches your gadget's description is an hideously overcomplicated form of EFIE with wide band O2 feedback. If that's the case, I can do the same thing (which is to burn less fuel compared to stock) that your gadget does, with a few comparators and a WBO2 gauge controller.

GREAT MISTAKE! DCD CONTAINS NO LEAN-BURN! DCD makes only mechanical
"misfire", which is not the chemical ones you expected. The magic feafure of
DCD is, althrough it is working under high-lambda control, but this is the
overall result detected from exhaust pipe, and observed by WBO2 sensor, yet
inside the individual cylinders, the burnings are always kept at lambda = 1.00.
So the there will be totally NO LEAN-BURN happened inside the cylinders.
Your worrys seem just to waste brain power, or to over-use your knowledge.
By applying high-lambda closed loop without adapting DCD? You will obtain
a tranditional lean-brun engine that has caused all of your headaches for
decades, and less useful these days. DCD NEVER needs your unreasonable
worryies because DCD is never related to LEAN-BURN mechanism!

We can feel that Mr. TCD is now changed into Mr. TLB, taking benefit of
Tranditional Lean-Brun(TLB) skill happened long ago, nothing new and worthy
to try. Could you offer us something newer?

[Heihetech]

Originally Posted by t vago

Engine misfiring is never good. You may claim otherwise, but it's never a good thing to have completely unburnt fuel-air mix exit the combustion chamber.

I know modern engine control theory, which is something you obviously have no clue of.

Look up OBDII codes P0300 through P0307, and tell me how they are generated.

USUALLY, we human being want to fool engine computer like ECU is because
we want to obtain some attractive feature like DCD. But we should NOT be
fooled ECU CODE like Mr. TLB did. ECU CODEs are up to human to interpret.
If you take OBDII codes P0300 through P0307 (Mr. TLB has missed P0308,
which indicates the 8th cylinder. Because DCD HAPPENS in every cylinder,
please don't miss the 8th one.) seriesly, you have been fooled by these
codes. They simply mean no burnings happens in certain cylinders. It's only
some mechanical difference, not the chemical disaster as you expected.
Great knowledge of lean-brun has let Mr. TLB worrying too much!

To DCD controlled engine, OBDII codes P0300 through P0308 could just
be interpreted like this ---- DCD is ON, and is in progress, and is happenning
in every cylinder, and NO cylinder had trouble to run DCD mode. So please
join me to welcome these codes, they don't kill anything, don't be fooled by
them. Mechanical "misfire" is absolutely not the same as chemical "misfire"
that needs to be worried a lot.

[Heihetech]

Originally Posted by t vago

If you can get a WBO2 sensor that is capable of significantly greater than 1.5 lambda, then I could at least think about your claims. However, as production WBO2 sensors do not go that high, I have to view your claim with no small amount of skepticism.

WBO2 sensor that is capable of significantly greater than 1.5 lambda? funny.
I have told everyone that WBO2 sensor could work in pure air. HOW HIGH is
THE LAMBDA there in our common air? INFINITY!!!

production WBO2 sensors do not go that high??? Please go to ask BOSCH,
infinity lambda is what BOSCH claimed, not me. I tested many of them.
They are true.

To Mr. TLB, greater than 1.5 lambda seems too high to rich. The truth in
DCD is we could go as high as we want. This reminds me the old sayings
about the early airplanes ----- "Heavier-than-air flying machines are
impossible." SO To Mr. TLB, it becomes ----- "Higher lambda engines are
impossible." Human history will tell that with DCD invention, lambda
could also fly high above where you expected, like airplane does these
days.

[Heihetech]

Originally Posted by t vago

Appeals to authority, such as this pathetic paragraph above, are typically used by people who have a weak argument to begin with. I could claim any number of things on the internet, but unless they're backed up by real-world results that others can repeat, the claims are worth nothing.

I'll put my own knowledge up against this gadget of yours any day, Heihetech. I don't need some fabricated award claim from a non-SAE sanctioned contest to do it, either. The internal combustion engine is inherently a thermodyamic beast, which is something you can't seem to fathom. In order to intelligently discuss any form of fuel savings from modifying the basic operation of a thermodynamic engine such as the internal combustion engine we're all familiar with, it's necessary to resort to thermodynamics. Otherwise, you will (and did) forget something crucial.

Here's a question for you, genius. Name all of the forms (not manufacturer trade names) of variable displacement that exist for the internal combustion engine.

As an inventor, I made DCD controller, and having it tested on real vehicles
for years. It is real-world results that others can repeat, not only claims on
the paper and internet. Thermodynamics is only a tool for the invention, it
self is not an invention.

SAE??? There was no such orgnization when Henry Ford had built his first
automotive vehicle. Why DCD invention should be limited by SAE?

Sorry, I'm not an expert of variable displacement engine. If you are, you
may show us something, letting us know how affordable it is. But as I have
told everybody, DCD does make engine displacement variable, only by most
affordable retrofitting, in time and expense.

How about your variable displacement engine? I wonder?

[George Tyler]

It will work: it is similar to a variable displacement but with the cut off cylinders Clapping! they are causing loss, but I think the overall effect is still positive. the savings come from reduced manifold suction, less pumping loss.
Funny, I was working on something like this myself, then came across this article on autospeed web site..... I feel cheated! haha, well you snooze you loose. I tried this at idle on my previa with an openguage, I disconnected 2 injectors. idle speed dropped a bit, but litres/hour hardly changed. then I realised, the open guage still thinks all 4 injectors are working! so consumption is actually 1/2. some of that will come from the lower idle speed though. that is worth having, even if it was just at idle. I have other control scemes though, not the wideband sensor. will talk about that a bit later.
I have patented some things before but don't want to get into that again, as soon as there is potential money around you have to fight off the sharks. if I post it here at least I can use it without others sueing me!

[Phantom]

Even though the engine is not running lean the air the catalytic converter sees is very lean and can harm the cat.

[Heihetech]

Originally Posted by Phantom

Even though the engine is not running lean the air the catalytic converter sees is very lean and can harm the cat.

I don't think so. Oxygen will not kill the cat, no harm done. Just think when
you release gas padel during cruise speed on general vehicles, fuel will be cut
out, pure air instead of exhaust will be pumped onto the cat. Such case
happens frequently during normal driving, does it kill the cat? NO！So please
don't worry, oxygen will not harm the cat. Something that does harm to the
cat is un-burned HC from lean burn, which will not be involved within DCD.

[Heihetech]

Originally Posted by George Tyler

It will work: it is similar to a variable displacement but with the cut off cylinders Clapping! they are causing loss, but I think the overall effect is still positive. the savings come from reduced manifold suction, less pumping loss.
Funny, I was working on something like this myself, then came across this article on autospeed web site..... I feel cheated! haha, well you snooze you loose. I tried this at idle on my previa with an openguage, I disconnected 2 injectors. idle speed dropped a bit, but litres/hour hardly changed. then I realised, the open guage still thinks all 4 injectors are working! so consumption is actually 1/2. some of that will come from the lower idle speed though. that is worth having, even if it was just at idle. I have other control scemes though, not the wideband sensor. will talk about that a bit later.
I have patented some things before but don't want to get into that again, as soon as there is potential money around you have to fight off the sharks. if I post it here at least I can use it without others sueing me!

Glad to see your experiment. By disconnecting fuel injectors, you just made
traditional cylinder deactivation in a fixed mode. This is the skill having tried
by many others for decades. There might be dozens of similar patents in
the database around world. Please don't forget fuel is closed loop controlled
by ECU. So when you cut fuel from these 2 injectors, ECU will try to
compensat the loop by adding more fuel into other injectors. The result
may not save fuel, but the extra fuel injected into the active cylinders will
not be fully burned, it becomes un-burned HC and CO, becomes emissions.

As I have mentioned, 50% deactivation to a 4-cylinder engine of Previa is
over-deactivation that makes the vehicle not drivable, or largely reduced
driving ability. When you want to stop over-deactivation, you have to stop
the vehicle and plug into the injector connectors again.... Many issues and
troubles may make your invention non-operable.

DCD will definitely let your dream become true. It will bring all the benefit
you have dreamed, with less issues and troubles you would encounter. When
you need it, just click the button to turn it on; when you don't need it,
just trun it off. The percentage of deactivation can be adjusted in multiple
steps according to your driving needs, making your engine power best match
the real driving needs without wasting extra fuel. DCD IS HIGHLY
RECOMMENDED TO SMART ECOMODDERS LIKE YOU!

By the way, please show us your patents and inventions, I wonder.

[George Tyler]

yes, that is true, but at idle it is open loop, also at full throttle. I am thinging of making a ECU that controls mixture by spoofing the O2 sensor.... it has a pam of throttle opening, manifold pressure, rpm etc and stores what the engine normally does, then with the cyl deactivation on it generates the O2 signal that makes the correct mixture.
Another way to do it is to have 2 separate exhaust systems, with the O2 sensor in only one that is not going to be deactivated. they can join further down