exhaust gas recirculation system EGR

[bluntmaster280]

What is the exhaust gas recirculation system for. wouldnt putting exhaust into my intake dirty up my combustion chamber? is it better to have it on or off? thanks

[TheNeedForZ]

it dilutes the intake charge so the combustion temperature/pressure is lower. It is meant to reduce NOx emission. It isn't helping performance.

[TheNeedForZ]

BTW, welcome to the forum and remember to use search function

[bluntmaster280]

thnx. i tried searching for it on forum but found nothing.

[dr_hunt]

That was big until they discovered that fuel management is the key to low emissions. EGR is total junk IMO.

[Guest ZFury]

it dilutes the intake charge so the combustion temperature/pressure is lower. It is meant to reduce NOx emission. It isn't helping performance.

[TheNeedForZ]

Are you trying to say something?

[Guest ZFury]

me? no.....

[TheNeedForZ]

good for you.

[stagefumer11]

 

 

Saying it doesnt. Ive beged to differ. i gained heaps of power when removing my EGR system. Could of been faullty, hard to tell tho

[briann510]

If you think introducing crap back into your intake charge is good for perfomance go for it. Its like second hand smoke. YOU DONT NEED IT!

[Guest ZFury]

Yeah', I know it is not. But it is like recycling.

 

I would remove my EGR if I planed on doing any more work to the car.

[briann510]

Yeah'' date=' I know it is not. But it is like recycling.

 

I would remove my EGR if I planed on doing any more work to the car.[/quote']

I recycle my alum cans and cardboard, not anything on my engine!

[Brad-ManQ45]

Actually guys, EGR is critical in the search for fuel economy with engines past the mid 80's.

 

Take the LT-1 for instance. By this time GM knew what they were doing with EFI, and through the use of EGR, they could advance the timing further at part throttle cruise and get better gas mileage.

 

EGR has never been used at full throttle on any car, so max power has never been affected by having EGR on the engine.

 

I will agree that at smaller throttle applications you don't have quite as much pep, and certainly, there is no arguing the fact that the system falls under the category of "more stuff to go wrong", but don't rip it out on a whim - especially if you're interested in emissions and economy with your performance.

[briann510]

I agree on the newer cars, but on older performance engines without computer controls it just aint the same. I for one am not interested in fuel economy or emissions of any kind on the cars I race.

[rayaapp2]

I suppose that is why EGR valves are still in use on most modern vehicles today even Diesel applications, because they want to reduce the nitrogens of Oxide and rob you of performance.

 

They are never suppose to be working at any time except cruise... They do clean up the nox, but they also lower the combustion chamber temp by adding in inert gas. This will prevent PREDETONATION. It will improve the emissions and keep your combustion chamber temperature lower. This is why diesels and forced induction engines have EGR valves and it is important to keep them in good working order. It doesn't help or hurt your performance. It does a little for the longevity of your engine though while keeping your engine's emissions clean.

 

I can't believe this is still being debated here. A quick search within the past 1.5 years will give you all the info you need about the EGR.

[dr_hunt]

Actually guys' date=' EGR is critical in the search for fuel economy with engines past the mid 80's.

 

Take the LT-1 for instance. By this time GM knew what they were doing with EFI, and through the use of EGR, they could advance the timing further at part throttle cruise and get better gas mileage.

 

EGR has never been used at full throttle on any car, so max power has never been affected by having EGR on the engine.

 

I will agree that at smaller throttle applications you don't have quite as much pep, and certainly, there is no arguing the fact that the system falls under the category of "more stuff to go wrong", but don't rip it out on a whim - especially if you're interested in emissions and economy with your performance.[/quote']

 

Here's a quote from a google search.

 

Actually EGR does nothing but hurt performance and fuel economy, it's just emission control.:banghead:

 

 

Quote from Mr. fixit.com

 

A short chemistry lesson is in order here. It was discovered way back when, that high combustion chamber peak temperatures (the really short duration high temperatures near the end of the combustion process) caused oxygen and nitrogen to combine chemically and form these oxides of nitrogen mentioned above. Most of the anti-pollution devices of the day did a pretty good job of reducing the other bad by-products of combustion, namely excessive hydrocarbons and carbon monoxide, however they tended to induce the formation of oxides of nitrogen. Something had to be done else we would all die of smog diseases.

 

The automotive engineers figured that they needed to do something to lower the peak combustion temperatures which only occurred under certain high load driving conditions. They figured they could do so at the expense of power and fuel economy but what the heck, ya can't have everything! If they could only add something to the combustion chamber that would act like sort of a fire extinguisher to cool the combustion temperatures that would do it.

 

So they invented a way to allow some very inert gas to get back into the combustion chamber only when needed. They needed a source of this gas - it wasn't air, cuz that contains oxygen and nitrogen which caused the problem in the first place. So they chose carbon dioxide. Where to get a supply of carbon dioxide . . . ??? Hmmmm, how about the exhaust system? That is mainly carbon dioxide and water (plus a zillion other noxious chemicals) Suppose we allow some of the exhaust gas to get back into the intake manifold under strict control and only when we need it? That would cool the combustion chamber and prevent the formation of the NoX. Maybe we should call it recirculated exhaust gas (REG??). But a guy named Reginald voted no cuz he didn't want his name associated with a car part, so they called it exhaust gas recirculation (EGR) since there was nobody around with that name.

[TheNeedForZ]

I suppose that is why EGR valves are still in use on most modern vehicles today even Diesel applications' date=' because they want to reduce the nitrogens of Oxide and rob you of performance.

 

They are never suppose to be working at any time except cruise... They do clean up the nox, but they also lower the combustion chamber temp by adding in inert gas. This will prevent PREDETONATION. It will improve the emissions and keep your combustion chamber temperature lower. This is why diesels and forced induction engines have EGR valves and it is important to keep them in good working order. It doesn't help or hurt your performance. It does a little for the longevity of your engine though while keeping your engine's emissions clean.

 

I can't believe this is still being debated here. A quick search within the past 1.5 years will give you all the info you need about the EGR.[/quote']

 

There is no such thing as "predetonation." Preignition, or detonation, not "predetonation"

[rayaapp2]

My bad your right. preignition would be the correct term.

 

Here's a quote from a google search.

 

Actually EGR does nothing but hurt performance and fuel economy' date=' it's just emission control.:banghead:

 

 

Quote from Mr. fixit.com

 

A short chemistry lesson is in order here. It was discovered way back when, that high combustion chamber peak temperatures (the really short duration high temperatures near the end of the combustion process) caused oxygen and nitrogen to combine chemically and form these oxides of nitrogen mentioned above. Most of the anti-pollution devices of the day did a pretty good job of reducing the other bad by-products of combustion, namely excessive hydrocarbons and carbon monoxide, however they tended to induce the formation of oxides of nitrogen. Something had to be done else we would all die of smog diseases.

 

The automotive engineers figured that they needed to do something to lower the peak combustion temperatures which only occurred under certain high load driving conditions. They figured they could do so at the expense of power and fuel economy but what the heck, ya can't have everything! If they could only add something to the combustion chamber that would act like sort of a fire extinguisher to cool the combustion temperatures that would do it.

 

So they invented a way to allow some very inert gas to get back into the combustion chamber only when needed. They needed a source of this gas - it wasn't air, cuz that contains oxygen and nitrogen which caused the problem in the first place. So they chose carbon dioxide. Where to get a supply of carbon dioxide . . . ??? Hmmmm, how about the exhaust system? That is mainly carbon dioxide and water (plus a zillion other noxious chemicals) Suppose we allow some of the exhaust gas to get back into the intake manifold [b']under strict control and only when we need it[/b]? That would cool the combustion chamber and prevent the formation of the NoX. Maybe we should call it recirculated exhaust gas (REG??). But a guy named Reginald voted no cuz he didn't want his name associated with a car part, so they called it exhaust gas recirculation (EGR) since there was nobody around with that name.

 

 

So please argue with me how that really affects the performance of your car...

Are your really going to notice the difference at cruise? On top of which a lot of manufactures engineer their cars with the EGR in mind. Take for example the KA series engines from the early 90's. The computers were bias lean. Lean at cruise + heat = preignition. The combustion chambers just got to hot. You would definately find this out the moment you EGR stopped working. All you would do is hear ping ping ping down the highway. I even owned a 240sx that suffered from this.

 

I'm no engineer; in fact for from it. So take this next part as a question from a youngster.

How is dumping a small amount of inert gas into the cumbustion chamber going to rob you of you MPG?

[dr_hunt]

My bad your right. preignition would be the correct term.

 

 

 

 

So please argue with me how that really affects the performance of your car...

Are your really going to notice the difference at cruise? On top of which a lot of manufactures engineer their cars with the EGR in mind. Take for example the KA series engines from the early 90's. The computers were bias lean. Lean at cruise + heat = preignition. The combustion chambers just got to hot. You would definately find this out the moment you EGR stopped working. All you would do is hear ping ping ping down the highway. I even owned a 240sx that suffered from this.

 

I'm no engineer; in fact for from it. So take this next part as a question from a youngster.

How is dumping a small amount of inert gas into the cumbustion chamber going to rob you of you MPG?

 

Well, here are a few questions; What energy can be derived from an inert gas in combution? What is the effect of an inert gas in combustion? What chemical compounds does an inert gas make during combustion?

 

The answers are pretty simple. 1. Zero 2. the effect is less room for air/fuel mixture, so lowers combution temp by occupying space that would normally be taken by air/fuel. and 3. None

 

So, if your inserting inert gas in your intake charge, you have no energy derived from it, less air/fuel to burn, and no chemical compounds to form.

Therefore you get less power per ignition stroke since it doesn't burn, less power per ignition stroke since there is less air/fuel in the cylinder and the most important, lower emissions.

 

The key words in the quote are "heavy load conditions". Simply, that can not be confused with cruising down the highway at light throttle. But even more important, if it is "on" at any time, your loosing power, period. So in a nutshell you loose performance any time it is "on". You can run what you want, the key to power is getting mixture into the cylinder, having an efficient combustion and getting the burned mixture out of the cylinder. All in the most efficient manner possible.