I don't understand why so many people think that it is good to block off the EGR when the benefits far outweigh the negatives. To begin with it does not even operate under wide open throttle. Under normal driving conditions it allows some hot combustion gasses to be returned through the intake to be reburned. It increases efficiency of the engine by doing so and reduces some exhaust pollution. It actually increase mileage when cruising at highway speeds and decreases the temperature of the combustion chamber.

Blocking it off is going to do away with all of these benefits and gain nothing and run the risk of having a poor running engine, lower mpg results and a hotter combustion chamber which in the long run will do potential damage to the engine.

Why? Because people don't like the looks of the EGR? Or What? Maybe they just don't understand.....?

[This message has been edited by Mike Murphy (edited 12-31-2008).]

Its alot faster without all of those emissions controls and crap on it.

The EGR system has no effect on power output of the engine at all because, as stated, it's inoperative at both wide open throttle and at idle. Therefore, it does not slow the vehicle down one tiny bit.

The typical reason for disabling the EGR system is because of the inability or unwillingness to keep it repaired/working properly. Being that it's only got three main parts and is easy to troubleshoot, I wonder why anyone would consider it easier to disable it rather than repair it.

To properly disable the EGR system the chip, or memcal, needs to be reprogrammed, otherwise there's a non-zero risk of detonation at part throttle cruise. Detonation often leads to engine damage, and though many claim to have experienced no damage running with an improperly-disabled EGR system they are typically unwilling to front the cash guarantee that those they advise won't experience any engine damage.

JazzMan

quote Originally posted by darkhorizon: Its alot faster without all of those emissions controls and crap on it.

That doesn't make any sense by itself.

We all want efficient engines if it doesn't rob power, but car manufacturers only need to make a car that passes EPA standards. They don't care about performance too much. Good marketing sells more cars than performance, for the majority of vehicles. A lot of emissions controls are crap, but so are a lot of laws. Getting rid of the controls isn't always a good thing, especially when your car was designed that way (ecm, etc). Just as poorly designed laws mess stuff up, so do poorly designed emissions controls mess cars up. Some stuff should be just removed from the car, but some stuff should just be modified. I don't know enough about the EGR, besides that it means "exhaust gas recirculator," but what you say, Mike, makes sense.

Does anyone else have some knowledge? Do our EGR's cut out at WOT? 2.5 & 2.8? Any test/data?

-Michael

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"A guy know's he's in love when he loses interest in his car for a few days." -Tim Allen

He who dies with the most toys... still dies.


Check out my restoration!

It's really not that simple as it only does good things.
EGR sole purpose is reduce emissions on older design motors. it in the overall picture of performance does NOTHING to help your motor aside from reduced HC and nox. there is your plus.
Here are the minuses:
1. introduces hot gases with reduced o2 to the engine. this results in slightly less power due to lack of o2, so the ecm reduces fuel load slightly.
2. Introduces unburnt HC into the intake path, which cna cause issues long term. the hc's that don;t make it in will carbonize and build up over time on the entire intake path.
3. Add some heating to the intake system which in turn lowers air density and therefore less available power.

Now the performance effects are not big numbers on most stock motors, but do have some effect on the power on reworked motors. Still small, but when you don;t have alot of power to begin with, it can help.
the egr system unless cleaned out isn't even working on most motors over 80k, as it is carbon fouled. since the ecm has no direct measurement of the valve on the older motors, you never know it. newer emissions systems do check that the valve is at least working mechanically. Newer still motors do not even use egr valves.

decide for yourself. on emisions checked vehicles with a good motor, the numbers posted are minimally differrent with it installed or blocked. If it it fails with it blocked or not working, there are bigger issues with the motor. before the rebuild I easily passed emissions, and the tube was completely blocked solild (120k on it) I had to use a drill and compressed air to open it when I did the rebuild. the numbers on the new motor where almost identical to the worn motor doen a few years earlier.

Well there's the issue right there. Do you want efficiency or power? With a stock 2.8, well I'll just say I want efficiency. I like the motor to run/car the way it was designed to run. It's plenty sporty for the way I drive.

Here's where I am coming from. I have a 88 Formula and an 86 SE. Up until recently, the 86 had all the usual PO fubar's including the blocked off EGR. Of course the way he had it blocked off was a major contirbutor to it's issues but this car was a constant battle. Eradic idle, surging at cruise, surging under acceleration, etc. etc. The car at it's best would only get 16 - 18 mpg. Just before my boy spun a bearing in it, I had done a lot of work to it. Got it running the way it was designed to run and was getting 25 plus mpg around town and 28 on the hiway.

Now in contrast, the 88 is a completely stock well cared for everythings working 65k mile car. When I 1st got it, it had an idle issue and an o2 issue. I replaced the o2 sensor and cleaned the IAC and the car runs perfect - no issues - get in turn the key and drive it. Gets 28 around town and 31-32 on the hiway. I believe that when you start deleting, disconnecting, adjusting things on the car, you just end up with headaches.

If I want to go fast and scare the hell out of myself, I get in my 47 Chevy with the 502, point it down a straight road and pull the trigger. Just my 2 cents anyway!

Happy New Year everyone!

Pat

quote Originally posted by JazzMan: The EGR system has no effect on power output of the engine at all because, as stated, it's inoperative at both wide open throttle and at idle. Therefore, it does not slow the vehicle down one tiny bit. The typical reason for disabling the EGR system is because of the inability or unwillingness to keep it repaired/working properly. Being that it's only got three main parts and is easy to troubleshoot, I wonder why anyone would consider it easier to disable it rather than repair it. To properly disable the EGR system the chip, or memcal, needs to be reprogrammed, otherwise there's a non-zero risk of detonation at part throttle cruise. Detonation often leads to engine damage, and though many claim to have experienced no damage running with an improperly-disabled EGR system they are typically unwilling to front the cash guarantee that those they advise won't experience any engine damage. JazzMan

As always, Jazzman hit the nail on the head... There are a lot of people that don't take into consideration the F/A mixture curve that's programmed into the ECM. The ECM actually expects those recirculating gases to be there, and as a result, leans out the mixture so as not to run it over-rich. As a result, simply blocking the EGR system WILL, and I repeat WILL cause damage from running the engine too lean for too long.
There is no performance advantage to be gained from blocking your EGR off, simply because it only operates at cruise speeds. WOT & idle, as stated, don't use the EGR, and thus your performance isn't hurt any whatsoever. In fact, the word performance refers to the well-being and operational characteristics of the engine, so by denying the EGR system and cutting out increased fuel efficiency, you're hurting the performance.

In my personal opinion, blocking off the EGR would be akin to forcing an auto transmission into lockup all the time... Yeah, you get less torque loss during acceleration, but look at the headaches!
Anyway, please don't block off your EGR, or if you do, at least have your chip re-programmed accordingly.

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Journal of a concept: http://southeastfieros.com >>> Build Thread >>> Parts thread (for project funding)

[This message has been edited by fieroboom (edited 12-31-2008).]

I understand that the EGR is real nice and improves fuel economy, emissions and stuff, but I blocked mine. To answer your question, I blocked it because the damn pipe was always cracked (vacuum leak) and every pipe that I got from the junkyard/ PFF member was also cracked. A new pipe is 100 bucks. Someday when i find 100 bucks under the mattress i'll buy the stainless braided pipe from the Fiero Store.

A good reason to block off the EGR is to run the 7730 ECM and not switch to digital EGR get a chip burnt and your good to go.

I want to do it just to eliminate all the crap under the lid. Be nice to pull out the solenoid and all the vacuum lines.

what about the 2.5 engines?
i hear there not ECM controlled.
would it make much of a difference it that one is removed/blocked off?
im just asking because my EGR is toast and i dont have any money to buy a new EGR.

I believe the real reason that people remove the EGR is to prevent dirty exhaust soot from entering the intake manifold. Whether this is benefical or not is debatable but the manifold does stay cleaner. I agree that the EGR valve is beneficial at cruise and part throttle conditions for all of the above reasons, but if you remove the EGR all you need to do is to readjust the fueling a bit and you're fine. If you don't reprogram then you could burn a piston.

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" THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
87GT - 3.4L Turbocharged engine, modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

Mostly because of emissions phobia

Joshh44 the duke is not fussy about the EGR.. you can block off the egr with a plate available at some parts stores or just make one..Block off EGR hole with a plate you make from sheet metal if not avail from parts house,,and plug vacuum
many of the duke EGR,s can be cleaned in a carb cleaner submerse 3/4 of it .. the egr,s have gotten expensive ,,one of the reasons many here eliminate them..
the duke EGR with the cork looking gasket can not be soaked ,,some of the after market can be soaked but should not be,,,When you push up the rod that sticks out the bottom ,,if the gasket is toast then you are crap out of luck..
if you are a true motorhead you can take a duke EGR apart and replace the gasket..
if the gasket is good and it take a firm pressure to push up the rod that lifts the diaphram, you should be able to resurrect your EGR..
a major cause of egr replacement is a bad vacuum leak,,make sure the hose is not harden where it connects
with faulty EGR always remove hose and plug and if car runs better it is EGR.
Keep the stock original as long as possible..I hate those washers on the replacements
make sure you do not have leak at gasket
sometimes a vacuum leak at brake booster or else where cause EGR problem..
In dogsled and eskimo country an egr can make your life easier but you can run with out one for a long time,,but a bad egr should be caped off & plugged ,, then replaced when financial windfall comes your way

[This message has been edited by uhlanstan (edited 01-01-2009).]

quote Originally posted by MordacP: I understand that the EGR is real nice and improves fuel economy, emissions and stuff, but I blocked mine. To answer your question, I blocked it because the damn pipe was always cracked (vacuum leak) and every pipe that I got from the junkyard/ PFF member was also cracked. A new pipe is 100 bucks. Someday when i find 100 bucks under the mattress i'll buy the stainless braided pipe from the Fiero Store.

Or get one of these. Then if it cracks, an inexpensive pipe from Lowes or Home Depot will replace it.

quote Originally posted by joshh44: what about the 2.5 engines? i hear there not ECM controlled. would it make much of a difference it that one is removed/blocked off? im just asking because my EGR is toast and i dont have any money to buy a new EGR.

The 87-88 DIS engines will ping under light acceleration if the EGR is disabled. There is no way to control the spark advance without reprogramming the PROM.

Also be careful if using carb cleaner around the EGR. The cleaner may damage the diaphragm.

Removing the EGR for "performance" is an "old school" method. The reason is back in the 70's when they started adding EGR's, Many blocked the port at the head/intake mating (The EGR port was part of the intake manifold on many engines) and retuned the carb because the port would heat up the intake manifold and thus the carb/intake air. It should also be noted that EGR ran off of a TVS switch so they operated based on temp and vacuum and were open at WOT. By blocking the port and the vacuum line the intake stayed cooler and the engine performed and ran better. However, This is not the case with later cars (1982 and newer) and EFI. The EGR only comes into play at specific programmed times and is closed during WOT.

quote darkhorizon:Its alot faster without all of those emissions controls and crap on it.

I have the emissions controls on both of my engines. I keep them clean clean and don't allow rodents to do their business on them.

You dont even have to buy the kit off ebay. I went to lowes and bought the fittings and the gas stove repair/replacement line and did it myself. The biggest cost was for a tap to convert the egr threads and the intake threads so that the fittings would screw in. If you do a search you will find this repair explained in greater detail.

The build up of the black gunk the egr leaves behind makes me think its a good idea to block it off.

If the gasket is good just clean the black residue by soaking the lower half ,,this is the devils work and we must all cleanse our self every few years to prevent the dreaded satan,s clogg..many of the wealthy forum members who have money to spend on cashmere nut warmers & 12,000 dollar Fiero,s do not understand the lowly peasant working class.. we are hoping one of you has a fender bender with us with your mistress in the car and you pay us off rather than file a report..on what happy days !!

quote The 87-88 DIS engines will ping under light acceleration if the EGR is disabled

what about the 84-86 engines? any side effects? or any long term effects?
i been reading so far on here that you can burn out a pistion?
would better plugs and a good tune burn all the fuel? so it doesnt have to recerculate?
or am i off on my thinking?

I removed my EGR the "right" way meaning I got a reprogrammed memcal.
My engine was working perfectly when I removed it and my milage is the same, no pinging, no issues.
I removed my EGR because I made a custom y-pipe routed a little different than stock and I want a cleaner looking engine.

quote Originally posted by joshh44: what about the 84-86 engines? any side effects? or any long term effects? i been reading so far on here that you can burn out a pistion? would better plugs and a good tune burn all the fuel? so it doesnt have to recerculate? or am i off on my thinking?

The ping in some engines on acceleration with a nonfunctional EGR is probably the result of the additional timing that exists at those EGR command points to cover the reduced combustible mixture. Fuel octane probably plays a part there also and the detonation probably wouldn't occur with premium gas. Otherwise anytime detonation exists on a regular basis there is a risk for piston damage. I certainly don't believe you can burn a hole in the piston without a very lean condition being present, with the EGR physically blocked the ECM will have to correct for the additional oxygen at those locations and if it can do so before being maxed out value wise you shouldn't see more than a rise in engine temps maybe, and an engine light if programming is designed to detect the mixture change.

84-86 engines were still using the electric carb in some applications and may respond in a manner that may very well have resulted in something more serious after a while, but for the most part the ECM is designed to either not permit the engine to run or compensate in an effort to avoid permanent damage where possible in the event of a sensor failure. This is based on my understanding of what I've read so far, it doesn't mean you have not heard correctly. If it works properly I see no sense in bothering it except to make it function better.

[This message has been edited by Joseph Upson (edited 01-02-2009).]

quote Originally posted by spark1: The 87-88 DIS engines will ping under light acceleration if the EGR is disabled. There is no way to control the spark advance without reprogramming the PROM.

Actually either 4-cyl and even the V-6 could have pinging if the EGR isn't disabled via the PROM.

Any engine with an EGR solenoid (or electronic EGR) that is controlled by the PCM/ECM needs to have the EGR programming turned off in order to properly remove the EGR and keep the engine from possibly pinging.

quote Originally posted by Oreif: Removing the EGR for "performance" is an "old school" method. The reason is back in the 70's when they started adding EGR's, Many blocked the port at the head/intake mating (The EGR port was part of the intake manifold on many engines) and retuned the carb because the port would heat up the intake manifold and thus the carb/intake air. It should also be noted that EGR ran off of a TVS switch so they operated based on temp and vacuum and were open at WOT. By blocking the port and the vacuum line the intake stayed cooler and the engine performed and ran better. However, This is not the case with later cars (1982 and newer) and EFI. The EGR only comes into play at specific programmed times and is closed during WOT.

Ok, I have a question - the EGR on the 4.9 is on the intake manifold, so would the 'rules' on the 70's engine apply? Probably not since it it ECM controlled, but it seems that Cadillac did some steps back in time with the 4.9 (EGR on manifold, AIC motor, etc).

quote Originally posted by Mickey_Moose: Ok, I have a question - the EGR on the 4.9 is on the intake manifold, so would the 'rules' on the 70's engine apply? Probably not since it it ECM controlled, but it seems that Cadillac did some steps back in time with the 4.9 (EGR on manifold, AIC motor, etc).

One drawback I recall from having the EGR on the intake manifold in addition to the heat it added was also the heat added to the cylinder heads as a result of the recirculation through them on the way to the intake. I recall being told it contributed to some early heads cracking among other things and is probably why GM did away with the EGR port altogether on the SBC Vortec heads. Attached directly to the exhaust and fed back through the intake is a much better method I believe.

quote Originally posted by joshh44: would better plugs and a good tune burn all the fuel? so it doesnt have to recerculate? or am i off on my thinking?

The purpose of the egr is not to re-burn unburned fuel, but rather to introduce burnt gases which will slow down the combustion in chamber. In other words there is less oxygen in the mix which in turn causes it to burn slower. Better plugs won't make a difference.
On my 84, 85, and 86 Dukes a non functioning egr was noticeable by the fact that I could hear the pinging at light to moderate throttle. The prolonged pinging will damage pistons and heads.

You should run the EGR,, but if youns is low on sheckles or hryvinias.a peasant can block this off and drive the car,,if there is serious ping then repair or replace

how to run duke with out EGR ,,run 89 octane & retard timming 1 to 2 degrees ,on the 87 ,88 you may have to run 92 if you havew serious ping you need to run EGR

A duke run with out an EGR must have no vacuum leaks,,IAC should be cleaned ,, because the egr is a controled vacuum leak !!
the after market EGR,s have a weaker rod spring and will not last as long as a delphi ot GM,,BUT the gm will lasy 250,000 miles if the gasket does not deteriorate
Plus the aftermarket units have the washers which are difficult to understand

[This message has been edited by uhlanstan (edited 01-02-2009).]

When I first went to remove my '84's valvecover the EGR was IN THE WAY! What the hec. Unless my EGR tube is bent, the designers put it just about 1/2" too far over the valvecover so that I have to remove the EGR just to open my valvecover. It's really ridiculous. Is my tube bent? ...'cause I'm surprised no one's mentioned this yet.

Merry Christmas, and a Happy new year.
-Michael

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"A guy know's he's in love when he loses interest in his car for a few days." -Tim Allen

He who dies with the most toys... still dies.


Check out my restoration!

Plus for the EGR:
Help emissions by reducing NOx
NOx: http://www.epa.gov/air/urbanair/nox/
Why? Because smog looks bad.

Negatives for the EGR:
Contaminates the intake tract with particles
Heats up the intake charge
The recirculated gases take up space in the cylinders that should other wise be given to air. (hurts VE)

Modern cars with variable cam timing often don't use an EGR but instead use the variable cams to cause exhaust to get sucked back into the cylinders.

I hadn't thought of this before, but could not having EGR increase highway fuel economy? I know most of my highway driving is done with very little throttle, which would be the time the EGR is used. I remember something about functional EGR allowing timing to be advanced, but does that make up for it?

quote Originally posted by Fierology: When I first went to remove my '84's valvecover the EGR was IN THE WAY! What the hec. Unless my EGR tube is bent, the designers put it just about 1/2" too far over the valvecover so that I have to remove the EGR just to open my valvecover. It's really ridiculous. Is my tube bent? ...'cause I'm surprised no one's mentioned this yet. Merry Christmas, and a Happy new year. -Michael

Your egr is normal. The duke doesn't have a "tube" per say. The valve is mounted on the intake to control the flow from the passage through the head into the intake

I have trueleo headers on my car the stock tube doesn't always line up and its a real pain to fabricate one. I passed emission with a lower ppm then a new fiero with a properly working egr.

quote Originally posted by Primaris: Plus for the EGR: Help emissions by reducing NOx NOx: http://www.epa.gov/air/urbanair/nox/ Why? Because smog looks bad.

No, it's not done for appearance. Smog is slang for visible pollution, but just as people in the past didn't believe in air because you couldn't see it there are still people who don't believe there is pollution just because it's not visible. But in fact, the oxides of nitrogen such as NO, NO2, NO3, etc. (collectively referred to as NOx) are fairly hazardous. They combine with moisture to form nitric and nitrous acids in your lung mucosa, eye and nasal membranes, etc. If there's fog they forn acid fog which etches paint and glass, as well as human and plant tissues. Constant exposure to NOx causes permanent lung damage, asthma, etc, even at fairly low levels. So, saying that the primary reason for reducing NOx is because it "looks bad" is completely ignoring the very real damage that oxides of nitrogen do.

quote Originally posted by Primaris: Negatives for the EGR: Contaminates the intake tract with particles Heats up the intake charge The recirculated gases take up space in the cylinders that should other wise be given to air. (hurts VE) Modern cars with variable cam timing often don't use an EGR but instead use the variable cams to cause exhaust to get sucked back into the cylinders.

The amount of heat recirculated back into the engine via EGR gas flow is miniscule and is probably only detectable with precision instrumentation. The reason is that the amount of exhaust gas recirculated is never more than a few percent of total air flow through the engine. Since the primary exhaust products of a properly functioning engine are CO2 and nitrogen, both in gaseous form, the amount of "particles" being run back through the engine are microscopic at best. The primary cause of so-called "black gunk buildup" in the intake is oil vapor from the PCV system, not exhaust gases.

The small amount of recirculated exhaust displaces air drawn in via the throttle body; the same amount of gas volume enters the cylinder regardless of what percentage of it came via the EGR valve vs the throttle body valve. VE won't be affected since pumping losses are the same upstream of the intake valve; if anything, VE might be improved a very tiny bit because exhaust gases are a PSI or two above ambient.

Bottom line: If you want to keep the intake pristine clean then remove the PCV system, but be prepared for significantly reduced engine life. The EGR systems as implemented on modern engines have no detrimental effects on power or efficiency.

JazzMan

I'm not the ultimate expert on this subject and most people have had some intelligent things to say on here as well, but there is a lot of mis-information that's also being passed around.

1 - There is NO performance gain by eliminating the EGR. The only gain you might see would be if you re-worked the intake and Y-pipe to eliminate the disturbance that's caused by the inlet / outlet of the EGR, which is negligeble, and 99% of the people on here who have removed their EGR simply block it off anyway.

2 - When running properly, it improves fuel economy under normal cruising speeds by re-introducing the exhaust gasses which may still contain unburned fuel gasses prior to the exhaust catalytic converter. This obviously improves emissions by ensuring a more complete burn, but also reduces the amount of oxygen / gas that is required in the combustion. At wide open throttle, the EGR closes anyway.

3 - It HAS in fact been proven to aide in the cooling of the piston tops by preventing a lean condition. I guess you could say that the ECM is programmed to use the recirculated exhuast gasses, so when they are NOT present, it's replaced with oxygen which in turn causes a lean condition.

4 - As mentioned in #3, the computer is designed to make use of this and without it, your engine will not run properly under normal driving conditions.

5 - The design of this EGR system is rather lame... the intake mounted ones typically are more efficient, but there are trade-offs... an intake mounted one typically means there is an exhaust runner in the intake leading to EGR, and therefore heats up the incoming air. In the case of our Fiero V6, the EGR is mounted way off on the Y-pipe so while it MAY be less efficient, the exhaust gasses have been given more time to cool and therefore give better performance over the other style. However, the performance we're talking about is at 1/4 throttle...


I think a lot of the old-school generation likes to remove it because they're tainted with all the crap that was shoved on cars in the late 70s and early 80s. IE: Smog Pumps... which are total crap. I dare, DOUBLE DOG DARE, anyone on here to tell me the benefits of a smog pump, air injection, and pellet cat configuration over a set of standard ceramic catalytic converters. The same people that pull those smog pumps off, are the same people that pull the EGR systems off.

Many of the newest cars are designed so well, and under far more advanced computer controll 128-bit OBD-2 like in the Solstice, which is better than the standard OBD-2 systems... that... many new cars run so efficiently that they don't even NEED EGR systems. I don't have one on my Solstice.

But I would never consider removing it on my Fiero. It does more harm than good.


The ONLY complaint I have is that it totally coats the inside of my intake with carbon and soot... which in turn leads me to have to use Seafoam on a regular basis. That IS a pain in the butt.

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Todd,
2006 Pontiac Solstice
2004 Volkswagen Beetle Convt. (Wife's)
2002 Ford Crown Victoria LX
1987 Pontiac Fiero SE / V6
1981 EZ-GO Xi875-A "Miami Dolphins" Medical Cart
1973 Volkswagen Type-2 Transporter
1973 Oldsmobile Cutlass Supreme 350

the "old" reason to remove/block off the EGR was this: the replacement tube was expensive. this is why I did it. I didnt want to spend $70 for a stupid tube I didnt really need. I just spent way to much on the engine, and this little detail didnt mean squat to me. gas was cheap, also. so - blocked the ports. I was getting a chip made anyways for the other works done, so $70 or $0 choice. easy 'nuff. no EGR

now, today - I am thinking of adding the EGR again. but, being I have headers with no bung on the y-pipe, and my intake has no bung for the EGR either - I am kinda stuck without. I have a 7730 ECM, and I do have the solenoid pack EGR valve. maybe come spring, I will cut the y-pipe hole & cut a intake hole. because I do want to get some decent milage. I rarely get past 20MPG.

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1985 Fiero SE - Plain Red 3.1 V6 Coupe
Engle18Cam DIS 4.10-4spd 7730 WCF Long Tubes Borla
D.A.M.M. - Drunks Against Mad Mothers

I believe that people falsely blame the EGR system for dirtying up their intake. The EGR system does a lot to cut emissions and it does improve gas milage a little. The thing that I hear most people complain about is grime coating the intake. The grime is made up of two things: carbon from the EGR system and oil from the PCV system. Remove either one and the grime goes away. The best solution IMO is to use an oil catch can on the PCV system.

how much does the EGR improve for MPG?

Stop the Greeness. No one is saying the EGR doesn't clean up NOx. Take the green blinders off.


If you think the EGR is performance hit free, then how does forced induction work? It adds more air into the cylinders there by increasing the power.

The EGR takes away air.

Now just like forced induction in order to gain the lost power you have to tune the engine (carb/ecu). The gains will be small, but they will be measurable.

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