EGR Valve, Do I Need This?
Thread Starter
Racer
Joined: Mar 2005
Posts: 294
Likes: 1
From: Racine Wisconsin
EGR Valve, Do I Need This?
I'm in one of those "while I'm at it" phases on my 1973 small block. I have decided to clean and repaint some of the engine components and got curious about the EGR. I verified that the EGR valve works but I wonder if it is really needed. I assume that a future replacement manifold would not have provision for EGR. My vehicle is registered as a "collector" and will not be smog checked. The car runs fine as is. Is there a performance downside or upside if the EGR is eventually removed? Thanks.
Pro
Joined: Apr 2008
Posts: 596
Likes: 6
From: Irving Texas
All the EGR does is open the exhaust passage into the intake passage.
The EGR problems come into play when it gets stuck open. If it gets stuck closed, it's like not having one at all.
In my experience, removing it and keeping your engine properly tuned and carb properly adjusted, you can pass a sniffer test all day long. I also used intake gaskets with exhaust heat crossover block-off passages.
Of course, alot of restoration purists will say that it is not factory correct or that the smog police will come and get you. I'm in Texas and my 1976 doest require a sniffer test, just a safety check (lights, horn)
The EGR problems come into play when it gets stuck open. If it gets stuck closed, it's like not having one at all.
In my experience, removing it and keeping your engine properly tuned and carb properly adjusted, you can pass a sniffer test all day long. I also used intake gaskets with exhaust heat crossover block-off passages.
Of course, alot of restoration purists will say that it is not factory correct or that the smog police will come and get you. I'm in Texas and my 1976 doest require a sniffer test, just a safety check (lights, horn)
Race Director
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From: Hartselle AL
St. Jude Donor '09
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Cruising
Joined: Apr 2010
Posts: 12
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From: At my Bar drinking and wrenching in Boulder Colorado
Still pretty much the same. If it is in proper working condition I wouldn't worry about it affecting performance too much. Removing it will give you a slight performance upside with and eco upside as well. Although there will be an increased NOx, Particulates, Carbon monoxide and Carbon dioxide are lowered. EGR removal allows an increase in fuel economy as high as 25%.
Last edited by Lars V2.5; Apr 3, 2010 at 01:37 PM.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
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From: At my Bar drinking and wrenching in Lafayette Colorado
So first you raise the 
flag, and then you agree with me. What's your deal?
The EGR on a C3 is hooked up to ported vacuum. Ported vacuum only exists at light throttle cruise, so the valve can only be opened at light throttle cruise. My statement was that the EGR has no effect on idle and WOT performance, which you then agreed with - if operating correctly, the valve is closed in both of those conditions due to lack of ported vacuum.
I never said the valve had no effect on cruise performance. I did not address mileage or contaminants at cruise.
There is no computer control of the EGR on a C3, so your comments are invalid - a C3 EGR is controlled by ported vacuum and the thermostatic switch.
Wow... you really are an ***. You're going to start picking on these guys' spelling and grammar on this Fourm? You're in for a rough ride. But in answer to your question, there would be a ' in EGR if the acronym is used in the possessive, such as, "the EGR's function is to..." There would not be a ' if it is used in the plural, such as, "I have two EGRs on my workbench." Hope that takes care of your concern. I'm sure BTAL appreciates the correction and that this is of great value to him.
flag, and then you agree with me. What's your deal?The EGR on a C3 is hooked up to ported vacuum. Ported vacuum only exists at light throttle cruise, so the valve can only be opened at light throttle cruise. My statement was that the EGR has no effect on idle and WOT performance, which you then agreed with - if operating correctly, the valve is closed in both of those conditions due to lack of ported vacuum.
I never said the valve had no effect on cruise performance. I did not address mileage or contaminants at cruise.
There is no computer control of the EGR on a C3, so your comments are invalid - a C3 EGR is controlled by ported vacuum and the thermostatic switch.
Wow... you really are an ***. You're going to start picking on these guys' spelling and grammar on this Fourm? You're in for a rough ride. But in answer to your question, there would be a ' in EGR if the acronym is used in the possessive, such as, "the EGR's function is to..." There would not be a ' if it is used in the plural, such as, "I have two EGRs on my workbench." Hope that takes care of your concern. I'm sure BTAL appreciates the correction and that this is of great value to him.
Last edited by lars; Apr 3, 2010 at 02:40 PM.
Safety Car
Joined: Jan 2008
Posts: 3,795
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From: Aarhus, Denmark
Still pretty much the same. If it is in proper working condition I wouldn't worry about it affecting performance too much. Removing it will give you a slight performance upside with and eco upside as well. Although there will be an increased NOx, Particulates, Carbon monoxide and Carbon dioxide are lowered. EGR removal allows an increase in fuel economy as high as 25%.
Melting Slicks
Joined: Oct 2005
Posts: 2,056
Likes: 8
From: Redruth Cornwall
Hey Lars, looks like you have earned yourself a stalker.... 
So removing the EGR will result in a performance upgrade, be better for the enviroment and save you on your gas bills? 25% increase in economy 
Still pretty much the same. If it is in proper working condition I wouldn't worry about it affecting performance too much. Removing it will give you a slight performance upside with and eco upside as well. Although there will be an increased NOx, Particulates, Carbon monoxide and Carbon dioxide are lowered. EGR removal allows an increase in fuel economy as high as 25%.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Are you Lars version 2.5? Same address and same drinking beer and wrenching. Very strange.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Cruising
Joined: Apr 2010
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From: At my Bar drinking and wrenching in Boulder Colorado
Race Director
Joined: May 2005
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From: Millington Illinois
St. Jude Donor '08-'09
Nope, he said it is only used during light cruise. How are you going to define light cruise? That's like saying we only use A/C at moderate temperatures. Just . Now lars is going 
over other people spreading and tells everyone he hates this forum because of . Also I said I was curious, I was not being a dick I just wanted to properly use the '. And to lars read "Computer controlled EGR's in C-3s?" "Nope not in a c3. By "newer" I was referring to newer cars not newer c3s. Just curious is there supposed to be a ' in EGRs?" before you say "There is no computer control of the EGR on a C3, so your comments are invalid"
Also Lars goes around spreading about Demon carbs having crap in them but if you get one from recent production and speak to BG you would know they now clean them and check them before shipping.
. Now lars is going over other people spreading and tells everyone he hates this forum because of . Also I said I was curious, I was not being a dick I just wanted to properly use the '. And to lars read "Computer controlled EGR's in C-3s?" "Nope not in a c3. By "newer" I was referring to newer cars not newer c3s. Just curious is there supposed to be a ' in EGRs?" before you say "There is no computer control of the EGR on a C3, so your comments are invalid"Also Lars goes around spreading
about Demon carbs having crap in them but if you get one from recent production and speak to BG you would know they now clean them and check them before shipping.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
I don't know why Lars takes this kind of abuse. He did for awhile and left but thankfully came back. Now .... ? If you wish to know how an EGR works I can do it with pics (EGR, TVS, ported vacuum, manifold vacuum, the whole nine yards). It will verify what Lars has stated. But the truth may be beyond your understanding.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
I'm in one of those "while I'm at it" phases on my 1973 small block. I have decided to clean and repaint some of the engine components and got curious about the EGR. I verified that the EGR valve works but I wonder if it is really needed. I assume that a future replacement manifold would not have provision for EGR. My vehicle is registered as a "collector" and will not be smog checked. The car runs fine as is. Is there a performance downside or upside if the EGR is eventually removed? Thanks.
Last edited by Paul L; Apr 3, 2010 at 07:51 PM.
Team Owner
Joined: Feb 2005
Posts: 32,519
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From: central America
St. Jude Donor '08-'09
Nope, he said it is only used during light cruise. How are you going to define light cruise? That's like saying we only use A/C at moderate temperatures. Just . Now lars is going over other people spreading and tells everyone he hates this forum because of . Also I said I was curious, I was not being a dick I just wanted to properly use the '. And to lars read "Computer controlled EGR's in C-3s?" "Nope not in a c3. By "newer" I was referring to newer cars not newer c3s. Just curious is there supposed to be a ' in EGRs?" before you say "There is no computer control of the EGR on a C3, so your comments are invalid"
Also Lars goes around spreading about Demon carbs having crap in them but if you get one from recent production and speak to BG you would know they now clean them and check them before shipping.
. Now lars is going over other people spreading and tells everyone he hates this forum because of . Also I said I was curious, I was not being a dick I just wanted to properly use the '. And to lars read "Computer controlled EGR's in C-3s?" "Nope not in a c3. By "newer" I was referring to newer cars not newer c3s. Just curious is there supposed to be a ' in EGRs?" before you say "There is no computer control of the EGR on a C3, so your comments are invalid"Also Lars goes around spreading
about Demon carbs having crap in them but if you get one from recent production and speak to BG you would know they now clean them and check them before shipping.
Drifting
Joined: Jan 2006
Posts: 1,540
Likes: 12
From: TX
Yes, you are being a dick, and an a$$. You joined today and come in this forum insulting others. I am sure you are a previous member that has had verbal battles you lost repeatedly with Lars, probably one of the idiots that made him want to leave in the first place. You need to change your name on this forum.
