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Discussion Starter · #1 ·
I picked up a 95 Caprice and i want to remove the EGR now, and wanted to know if it will screw anything up. since I know LT4's didn't have them
 
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Discussion Starter · #2 ·
Why do you want to remove it? It doesn't affect WOT performance and it improves part-throttle fuel efficiency and emissions.

The reason the LT4 doesn't have/need an EGR valve is because the LT4 cam has enough overlap that it has a natural EGR effect at lower RPMs.

Will it screw anything up? Not really. You might get some part-throttle pinging.
If you remove the valve but leave the EGR solenoid on, you might get a CEL. When the PCM opens the EGR valve it expects to see a certain amount of change in the manifold pressure. If it doesn't see a change, it'll throw a code.
If you remove the solenoid too, you will get a CEL for a bad solenoid coil.
 
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Discussion Starter · #3 ·
I'm glad you asked. I've been wondering too and I had a feeling it would be this kind of answer. If there was a gain to be had it would probably be in everyones sig. ;)
 
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Discussion Starter · #4 ·
fuel effeciency i don;t care, if the car was a daily driver then yea i would keep it in, but i an trying to get rid of clutter, and i was thinking about the EGR
 
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Discussion Starter · #7 ·
There will be no power gains at wot since the egr is disabled above 2400 rpms. It will make low throttle driving smoother assuming there is no pinging.
 
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Discussion Starter · #10 ·
I took my EGR off, the POS cooked the back of my intake manifold and caused a massive oil leak. Anyone ever look at how much area there is inside the manifold for the EGR passage? It heats the manifold and that's not good for performance. Sure the EGR shuts at WOT but the manifold has to take time to cool down. I checked with datamaster and I didn't see any more than the usual number of knock counts.

How did they keep cars from pinging at part throttle before they started installing EGR at the factory?

I look at milage by enjoyment per gallon.n If the car sucks gas I don't enjoy that, but if it hauls ass and gets decent fuel economy I think thats good economy.
 
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Discussion Starter · #15 ·
If you got a cam with a 200 or more degrees of intake duration remove the egr. I believe all common aftermarket cams fall into this category. This is done for driveability, not performance reasons.
 
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Discussion Starter · #17 ·
I think you should remove it when you get tired of fixing the manifold leak. Just like I removed the cat after the ignition screwed up and the cat glowed red hot, don't need something that will set my car on fire when the ignition screws up. if it's not on the car it can't cause problems.
 
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Discussion Starter · #18 ·
Originally posted by Ram Air 9C1:
This is done for driveability, not performance reasons.
Yup, EGR can be a source of a surge when you have a cam with enough overlap to create its own "internal" EGR.

Don, there's a timing compensation table in the PCM for EGR...it adds spark when EGR is commanded. I can help you delete it the right way if you want...ie fully disabling it in the PCM.

Quick 'n' Dirty, as with any mod to the fuel injection system or anything more than a minor minor bolt on, when you change the program in the PCM for the mod you disable the check engine lights accordingly. Don's equipped to program his own cars. It's just a couple checkboxes and a few settings to change (the spark compensation and the constants for EGR enable/disable).
 
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Discussion Starter · #19 ·
Originally posted by Mike454SS:
Don, there's a timing compensation table in the PCM for EGR...it adds spark when EGR is commanded. I can help you delete it the right way if you want...ie fully disabling it in the PCM.
Would it make sense to zero out this table with an aftermarket cam and !EGR? I don't think extra timing is going to hurt anything if there is no pinging. Just want to make sure.
 
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