EGR system removal?
Thread Starter
Heel & Toe
Joined: Apr 2011
Posts: 19
Likes: 0
From: Florence AL
EGR system removal?
I'm running a factory '77 L-82 4-speed. Are there any performance gains from removing the EGR system all together? Engine is completely factory.
What problems might be associated with this? (I'm in Alabama so no legal worries)
Sorry for the dumb question, I'm new at this.
What problems might be associated with this? (I'm in Alabama so no legal worries)
Sorry for the dumb question, I'm new at this.
Thread Starter
Heel & Toe
Joined: Apr 2011
Posts: 19
Likes: 0
From: Florence AL
Thanks guys. If I replaced the current hardware with an edelbrock performer rpm intake and a Holley carb that didn't have egr would that cause any problems with the rest of the motor? do replacement parts need to be egr equipped?
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Le Mans Master
Joined: Oct 2007
Posts: 7,459
Likes: 979
From: RI, Now Franklin/Nashville TN
EGR valves do nothing but hurt performance and are designed solely for emissions reasons. The concept that a EGR valve will not hurt the performance characteristics of an engine is false. It will introduce superheated dirty air into the intake charge causing elevated combustion chamber temperature, detonation, higher coolant temperature, poor driveability characteristics, and will decrease the available power of the engine under most operating conditions. There is a reason that performance engine builders do not include an EGR valve under most circumstances if they do not have to. They can also decrease fuel economy! Leave it off if you can.
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
EGR valves are a performance disaster. I naively thought I could build a performance motor with the EGR valve in place. You can't. I tried for about five years before I finally gave up. I could't control the detonation. I finally pulled the whole system off and the engine immediately ran better. Unfortunately the attempt took out my bearings and I ended up rebuilding the motor a couple of years later. Learn from my mistake!
Race Director
Joined: Jul 2001
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Drifting
Joined: Aug 2005
Posts: 1,682
Likes: 3
From: League City TX
It will introduce superheated dirty air into the intake charge causing elevated combustion chamber temperature, detonation, higher coolant temperature, poor driveability characteristics, and will decrease the available power of the engine under most operating conditions.
The whole purpose of the EGR system was to reduce the formation of nitrogen oxides.
It did this by lowering the combustion temperatures below the temp where they are formed.
When operating correctly the EGR reduces an engines tendency to ping at part throttle.
At full throttle, of course it affects nothing because it isn't active then.
Le Mans Master
Joined: Oct 2007
Posts: 7,459
Likes: 979
From: RI, Now Franklin/Nashville TN
Someone explain how introducing superheated previously partially burned hot exhaust gases in place of pure fresh cool intake charge reduces intake temperature? Why do EGR valves have a tendency to increase detonation if the valve cools the intake charge?
I would not run an EGR valve under any circumstances unless you have to-just my preference. You can choose what you want to do.
I would not run an EGR valve under any circumstances unless you have to-just my preference. You can choose what you want to do.
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
The EGR system does not raise combustion temperatures. It actually lowers them.
The whole purpose of the EGR system was to reduce the formation of nitrogen oxides.
It did this by lowering the combustion temperatures below the temp where they are formed.
When operating correctly the EGR reduces an engines tendency to ping at part throttle.
At full throttle, of course it affects nothing because it isn't active then.
The whole purpose of the EGR system was to reduce the formation of nitrogen oxides.
It did this by lowering the combustion temperatures below the temp where they are formed.
When operating correctly the EGR reduces an engines tendency to ping at part throttle.
At full throttle, of course it affects nothing because it isn't active then.
As for how much power you can expect, that depends on how the engine was built. On a stock engine, you won't see a lot of performance improvement. There are too many other problems with these engines stock. Remember in the seventies the engineers were scrambling to reduce emissions because of government regulation. They were throwing systems on there to get the cars into showrooms that just didn't work. Compression was too low and carburetors were too lean. EGR valves were just part of that package. If you want your engine to run correctly, you need to fix all that stuff.
Le Mans Master
Joined: Oct 2010
Posts: 6,943
Likes: 850
From: melbourne florida
2023 C3 of the Year Finalist - Modified
chicken lickin said that henny penny said that the sky is going to fall! i can imagine where this stuff comes from. like the pinheads who say a 160 degree thermostat will burn up my computer controlled engine, well it didn't on my mark 220k and going my 250 econoline 380k my 88 trans- am 320k .people are "educated" way beyond thiere intelligence
Drifting
Joined: Aug 2005
Posts: 1,682
Likes: 3
From: League City TX
Here is some good EGR reading http://autorepair.about.com/od/gloss..._egr-valve.htm
A couple of good quotes from the document-
Pg 1- The EGR reduces NOx production by recirculating small amounts of exhaust gases into the intake manifold where it mixes with the incoming air/fuel charge. By diluting the air/fuel mixtures under these conditions, peak combustion temperatures and pressures are reduced, resulting in an overall reduction of NOx output.
Pg 2- If too little EGR flows, the engine may knock and will not meet strict emissions standards.
I use to see this stuff on a pretty regular basis back in the 80s. An EGR valve would get plugged from carbon and the car would start pinging under light to moderate throttle. You could clear the EGR passages and stop the pinging.