egr removal 92
Safety Car
Joined: Feb 1999
Posts: 3,504
Likes: 4
From: Mexico Beach FL
If your engine (in particular, the cam) is stock, it is best to keep the EGR because:
1) It doesn't hurt performance, at wide-open-throttle, it is turned off by the ECM anyway.
2) Some vehicles experience detonation without EGR, because the EGR keeps the peak combustion chamber temperature down and prevents it.
3) Obviously, emissions.
There normally isn't any compelling reasons to eliminate it, but there are some good ones to keep it.
But, if you have a performance cam that has enough overlap to give you "internal" EGR, I do wonder if you could have too much EGR.
The LT4 doesn't have an EGR system because of the cam.
Tom Piper
1) It doesn't hurt performance, at wide-open-throttle, it is turned off by the ECM anyway.
2) Some vehicles experience detonation without EGR, because the EGR keeps the peak combustion chamber temperature down and prevents it.
3) Obviously, emissions.
There normally isn't any compelling reasons to eliminate it, but there are some good ones to keep it.
But, if you have a performance cam that has enough overlap to give you "internal" EGR, I do wonder if you could have too much EGR.
The LT4 doesn't have an EGR system because of the cam.
Tom Piper
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
I ain't arguing with anyone and the aforementioned reasons to keep it are valid.
But, I'm not running EGR on my 355 TPI engine in my old '73 Super Cheyenne truck. Engine runs GREAT. No pinging (although I always run 91 RON)
It doesn't have all those sooty,nasty deposits in the intake tract either.
Don't have it on my '84 Vette either. It runs GREAT and seems to have never missed having it.
Still have it on my '91 Vette but it's not going to be there much longer.
It makes the intake tract look like Hiroshima after the bomb. N-a-s-t-y.
Reintroducing into my engine stuff that's supposed to go out the tailpipe can't be something that I REALLY want.
I know the bennys of running it and have read all the reasons and most point to reduced NOX emmissions.
Not to appear to be unkind to the environment but the air quality in my part of the country is way up there with the best of'em.
A little more NOX from the exhasust of my Vette, that gets driven once a week at best, isn't going to kill any trees,pets or humans.
It's not going to destroy the ozone as much as those big Stupid Ugly Vehicles either.
Flame suit on.
Edit: Uh-Oh, I DO have that 'Internal EGR' thing on my truck that Tom talks about in his post . Gotta LOVE that idle sound!!
But, I'm not running EGR on my 355 TPI engine in my old '73 Super Cheyenne truck. Engine runs GREAT. No pinging (although I always run 91 RON)
It doesn't have all those sooty,nasty deposits in the intake tract either.
Don't have it on my '84 Vette either. It runs GREAT and seems to have never missed having it.
Still have it on my '91 Vette but it's not going to be there much longer.
It makes the intake tract look like Hiroshima after the bomb. N-a-s-t-y.
Reintroducing into my engine stuff that's supposed to go out the tailpipe can't be something that I REALLY want.
I know the bennys of running it and have read all the reasons and most point to reduced NOX emmissions.
Not to appear to be unkind to the environment but the air quality in my part of the country is way up there with the best of'em.
A little more NOX from the exhasust of my Vette, that gets driven once a week at best, isn't going to kill any trees,pets or humans.
It's not going to destroy the ozone as much as those big Stupid Ugly Vehicles either.
Flame suit on.
Edit: Uh-Oh, I DO have that 'Internal EGR' thing on my truck that Tom talks about in his post . Gotta LOVE that idle sound!!
Last edited by VetNutJim; Feb 11, 2005 at 09:37 AM.
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
I took all that stuff off my 92 but I also put on long tube headers that didn't have the EGR provisions and put in the LT4 hot cam kit. I guess all it would involve is unplugging your air pump, removing all the EGR tubes, blocking both EGR ports on the back of the intake with bolt on plates, and blocking the EGR ports on your manifolds with plugs. Then your ECM will throw a service engine code and to get rid of that you'll need to have a chip burned that has the EGR deleted.
Team Owner
Joined: Sep 2003
Posts: 25,295
Likes: 4
From: I'm the walkin dude I can see all of the world...
St. Jude Donor '03
You know what is hard to come by in these cars? Room to work.
Removing EGR/AIR might not give any power but it damn sure makes everything in the engine compartment easier to work with. I am very happy now that my system is gone for good. (Just my opinion and I'm not trying to start a war ) My engine does not ping and runs correctly w/o it also. 
You have to get custom tuning to tell the ECM the EGR/AIR stuff is gone so it won't throw a code. Forum member Ski_Dwn_it can burn your chip in your ECM to remove this system. I would contact him. After that, trace all the parts of the system and get rid of em. The M-22 Oil drain plug is the only thing I found which fit the holes in the manifolds. You can get it at Napa.
Removing EGR/AIR might not give any power but it damn sure makes everything in the engine compartment easier to work with. I am very happy now that my system is gone for good. (Just my opinion and I'm not trying to start a war
) My engine does not ping and runs correctly w/o it also. You have to get custom tuning to tell the ECM the EGR/AIR stuff is gone so it won't throw a code. Forum member Ski_Dwn_it can burn your chip in your ECM to remove this system. I would contact him. After that, trace all the parts of the system and get rid of em. The M-22 Oil drain plug is the only thing I found which fit the holes in the manifolds. You can get it at Napa.
Burning Brakes
Joined: Aug 2004
Posts: 1,110
Likes: 1
From: Geneseo Illinois
St. Jude Donor '06
As part of my engine upgrade ('90, L98, 383) i am eliminating the EGR, the air pump, the air pump solenoid plastic box, associated plumbing, the stock exhaust with all those valves and the tubes around the plugs, the TB heater, etc. etc. I can't wait to see how much better the engine bay will appear and how much easier it will be work on the engine or just change spark plugs.
I DO care about the environment, but the car is not a daily driver.
Mark
I DO care about the environment, but the car is not a daily driver.
Mark
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
Originally Posted by VictorRussell'92
After that, trace all the parts of the system and get rid of em.
on there I probably need to pull off. I was looking at it and I wasn't really sure what the heck anything was so I was afraid to take stuff off 
It was funny after the EGR stuff was removed and I was driving around with my new engine I hear this high pitched whistling noise and I'm like WTF is that? I looked and it was the air pump running because it was still plugged in it was just pumping air nowhere. 
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Team Owner
Joined: Sep 2003
Posts: 25,295
Likes: 4
From: I'm the walkin dude I can see all of the world...
St. Jude Donor '03
Originally Posted by ToyC4
I've still got the electric air pump and a bunch of other crap (tubing etc) on there I probably need to pull off. I was looking at it and I wasn't really sure what the heck anything was so I was afraid to take stuff off It was funny after the EGR stuff was removed and I was driving around with my new engine I hear this high pitched whistling noise and I'm like WTF is that? I looked and it was the air pump running because it was still plugged in it was just pumping air nowhere.
on there I probably need to pull off. I was looking at it and I wasn't really sure what the heck anything was so I was afraid to take stuff off It was funny after the EGR stuff was removed and I was driving around with my new engine I hear this high pitched whistling noise and I'm like WTF is that? I looked and it was the air pump running because it was still plugged in it was just pumping air nowhere. Yeah 92's even have a specific little fella under the ASR which you can pull along with the AIR pump. I put my MSD ignition where the electric AIR pump used to be!
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
Originally Posted by reed62783
thx guys. my car isnt stock so i think ill be ok. the egr crap is coming off b/c its always in the way. as far as the chip reburning- i can get a custom tune by fast.
Instructor
Joined: Oct 2004
Posts: 202
Likes: 0
From: OKC Ok
Also interested
I want to do the egr delete thing too. I don't know alot about it though. My car is a L98, 91. would the procces be the same as the 92, is there mabey any pics anywhere that I could take a look at or anything?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by 93JetJocky
From what I've read, the EGR valve is there to make the engine meet cold start emission requirements.
The AIR pump introduces fresh air into the exhaust to heat up the cats faster.
The EGR is used whenever to keep combustion temps down and reduce NOX emissions.
Burning Brakes
Joined: Feb 2003
Posts: 1,144
Likes: 18
From: Panhandle FL
I took mine off when I installed my LT headers. I've got 2 big boxes full of EGR lines, air pump, stock manifolds, cats, ect. I swear I shaved 50+ lbs of weight. As far as emissions, would you drive a 427 tri-power if you had one? I'm sure our computer controlled 350 with EGR delete is still cleaner than those. 
Race Director
Joined: Aug 2003
Posts: 13,421
Likes: 8
From: Lake Mary Florida
What I read was from the service manual. It says the Exhaust Gas Recirculation (EGR) system is used to lower NOx (Oxides of Nitrogen) emission levels caused by high combustion temperature and excessive oxygen. It does this by decreasing combustion temperature and displacing oxygen. The valve feeds small amounts of exhaust gas back into the combustion chamber. The EGR valve is usually open during warm engine operation and when the vehicle is above idle. Symptoms of faulty EGR is engine stops after cold start, engine stops at idle after deceleration, vehicle surges during cruise, and rough idle.
The Secondary Air Injection (AIR) system helps reduce Hydrocarbon (HC), Carbon Monoxide (CO) and Oxides of Nitrogen (NOx) exhaust emissions. It also heats up the three-way catalytic converter quickly on engine start-up so conversion of exhaust gases can occur sooner.
I'm not sure where I read that about it helping improve emissions on cold start.
The Secondary Air Injection (AIR) system helps reduce Hydrocarbon (HC), Carbon Monoxide (CO) and Oxides of Nitrogen (NOx) exhaust emissions. It also heats up the three-way catalytic converter quickly on engine start-up so conversion of exhaust gases can occur sooner.
I'm not sure where I read that about it helping improve emissions on cold start.
Drifting
Joined: Feb 2004
Posts: 1,485
Likes: 2
From: Champaign, IL
St. Jude Donor '05
Originally Posted by SPEED750
As far as emissions, would you drive a 427 tri-power if you had one? I'm sure our computer controlled 350 with EGR delete is still cleaner than those.
well said!
Safety Car
Joined: Feb 1999
Posts: 3,504
Likes: 4
From: Mexico Beach FL
I looked at it this way for my LT1.
The reasons not to eliminate the EGR or AIR:
1) Emissions
2) Doesn't hurt perfomance at all.
3) Federal law against it -- probably would never get caught, but not worth it since it doesn't hurt anything. Could get fined even in a state without emission inspection.
4) Resell value.
5) My state may someday start to require emissions inspection.
The reasons to eliminate it:
1) With performance cam, may have too much EGR -- this is the only reason I considered.
2) Easier to work around -- not very compelling to me.
3) Weight reduction -- since I don't race, I would be interested in lbs not ounces in weight reduction.
Tom Piper
The reasons not to eliminate the EGR or AIR:
1) Emissions
2) Doesn't hurt perfomance at all.
3) Federal law against it -- probably would never get caught, but not worth it since it doesn't hurt anything. Could get fined even in a state without emission inspection.
4) Resell value.
5) My state may someday start to require emissions inspection.
The reasons to eliminate it:
1) With performance cam, may have too much EGR -- this is the only reason I considered.
2) Easier to work around -- not very compelling to me.
3) Weight reduction -- since I don't race, I would be interested in lbs not ounces in weight reduction.
Tom Piper
Last edited by Tom Piper; Feb 13, 2005 at 09:11 AM.
