The Oldsmobile Connection

[sean000]

I am thinking about putting an aftermarket edelbrock intake on my 231, but they are not equipped with EGR. Should I expect to have any problems without the EGR. Will there be an effect on gas mileage?

Thanks,

By the way it is a vacuum operated egr.

[91parkave]

The EGR realisticly dosent do anything but help on emissions a little otherwise all it does is build up carbone in your intake manifold and create higher intake temps, IMO get rid of it.

[andrewk]

sean000 wrote: I am thinking about putting an aftermarket edelbrock intake on my 231, but they are not equipped with EGR. Should I expect to have any problems without the EGR. Will there be an effect on gas mileage?

Thanks,

By the way it is a vacuum operated egr.

So long as your area does not test for emissions, or require you to have factory equipment, you can remove it with no ill effects. EGR stands for Exhaust Gas Recirculation, meaning it lets exhaust fumes back into the intake tract so they can be re burned through the engine. What you have on your car is probably a single diaphragm EGR valve, and it should be using ported vacuum to open up. When you transfer things over from the intake, you will want to plug the port it is using, or if that is the only thing going to that port, eliminate the port with a brass plug. It will also help you to draw a diagram for all your vacuum operated accessories when you do the swap. The ports probably won't end up in exactly the same spot, but you will know what goes approximately where.

The effect on gas mileage should be minimal, but I would expect it to go down with the new intake, since it will flow a bit better than the stock unit.

[88 Coupe]

Quote: ........ Should I expect to have any problems without the EGR .........
You will need to retard the timing slightly and you might lose a little power because of it. It may, or may not, compensate for any gain from the carb/manifold change.

Quote: ........ Will there be an effect on gas mileage? ........
That will depend which carb you use, how it is jetted, and how heavy your foot is.

Norm

[88 Coupe]

91buickman wrote: The EGR realisticly dosent do anything but help on emissions a little ........
Yeah, right. Nothing but control detonation (ping) by injecting small amounts of exhaust, into the combustion chamber. Cools the charge, so it can tolerate more ignition advance, and raise the cylinder pressures.

91buickman wrote: ........ otherwise all it does is build up carbone in your intake manifold ........
If you had carbon buildup, in yours, you have other, unrelated, issues. But we already know about those, don't we.

91buickman wrote: ........ and create higher intake temps ........
Temps will not go any higher, there is not enough exhaust gas involved.

91buickman wrote: ........ IMO get rid of it.
Why are we not surprised.

Norm

[91parkave]

Right....so explain how any amount of exaust mixed in with the intake air charge will COOL it....Then explain why most people get rid of their EGR setups when upgrading?.

[andrewk]

91parkave wrote: Right....so explain how any amount of exaust mixed in with the intake air charge will COOL it....Then explain why most people get rid of their EGR setups when upgrading?.

A bit of formal automotive education would do you wonders I think. I'll explain as best I can.

EGR works by recirculating a small portion of exhaust back through the engine via the intake tract. This mixes with the incoming fuel/air charge and this recirculated exhaust dilutes the fuel/air mix with the inert exhaust gas, which in turn lowers the adiabatic flame temperature. (Adiabatic means "no heat transfer" in layman's terms, but it is really more complicated than that) This recirculated exhaust gas does not burn again, and this chemically cools the combustion charge by a few hundred degrees.

Typically, 5 to 10 (in some designs this could be more) percent of the exhaust gas is sent back to the intake as EGR (so 5 to 10 percent of the mixture entering the cylinders is exhaust). The amount of EGR the engine uses is limited because the fuel/air mixture needs to keep a consistent flame front during combustion. If you have too much exhaust going to EGR, it will result in misfires, and partial burns, which are one of the many things that can lead to carbon buildup. Other reasons for carbon build up include, but are not limited to- mis-adjusted choke, and improper fuel mixture- There are many others too, but we don't need to get into them now.

Since EGR chemically slows combustion, you compensate for it by advancing spark timing. This increases cylinder pressures, and will improve engine efficiency. There are other benefits to be had to, such as reduction of partial throttle losses, and decreased thermal losses, but we don't need to get into it at this point.

There are different reasons for removing the EGR setup- Some are good, and some bad. When one reaches a performance level where EGR no longer helps improve engine efficiency, or where engine efficiency is not a concern, it is usually removed. These applications are usually seriously modified engines, not just intake swaps or "P&P LIM,S2 TB,cusom 1/ 3/4 headers Modified S1 UIM", etc.

There is probably a greater number of people that think removing the EGR is going to give them "more performance" on their street car, or that it is a useless device. These examples are bad reasons. In a stock or near stock application, removing the EGR valve does little to nothing for your engine, and any gain you might realize from removing it is negligible at best, if there is a gain at all. Of course, the ass-dyno begs to differ...

Andrew

[91parkave]

Yea thanks for repeating what norm already said, I know how they are supposed to work, i know what they do in "application", but that is hardly the case in a real world app, while being true , the car being stock would have no gain from the EGr removed, but also there would be no loss, and this has been proven by many people including myself, still had the same amount of spark advance, the same 02 counts, the same gas mileage, still passed emissions with around the same thresholds. now you can take that for whats its worth but in the long run eventually having to replace the EGR because they do fail, just add's unneccecary maintnence for something that has no real-world affect on the cars performance and durability. Thats why i say toss it. Now diffrent folks diffrent strokes, some people keep them, some dont what the op does is up to him.


BTW: my mods have nothing to do with my stand on EGR systems...but nice try,

[andrewk]

91parkave wrote: Yea thanks for repeating what norm already said
I know how they are supposed to work, i know what they do in "application"

If you knew how they work, you wouldn't have asked the question. That leaves us with two ways to take that statement. Either you are lying, or you are trolling.

91parkave wrote: but that is hardly the case in a real world app, while being true , the car being stock would have no gain from the EGr removed, but also there would be no loss,

We've been over that already. Denial does not disprove existence.

91parkave wrote: and this has been proven by many people including myself,still had the same amount of spark advance, the same 02 counts, the same gas mileage, still passed emissions with around the same thresholds. now you can take that for whats its worth

Care to support that "research"? Right now its worth squat, especially considering you are implying that "many others" have cars set up like yours, which I can hardly believe passes emissions. Personally, I don't think there can be that many like you out there.

91parkave wrote: but in the long run eventually having to replace the EGR because they do fail, just add's unneccecary maintnence for something that has no real-world affect on the cars performance and durability.

If you have problems with the EGR failing, you have other problems with your engine. I have 172000 miles on my original EGR valve, with no problems.

91parkave wrote: Thats why i say toss it. Now diffrent folks diffrent strokes, some people keep them, some dont

It's hardly about difference of opinion. Facts are facts, and you can't fudge on them.

91parkave wrote: what the op does is up to him.

Which is why I have made sure he is provided with accurate information to better make his decision.

91parkave wrote: BTW: my mods have nothing to do with my stand on EGR systems...but nice try,

I never said it did. I was using your list of jury-rigged modifications to point out that it is still in a near stock state, using your conglomeration of different OEM parts and "cusom" mods. My statement never questioned your "stand" on EGR systems.

[88 Coupe]

sean000 wrote: ........ is a vacuum operated egr.
They all are. You can remove and plug the hose, to disable it, then test drive it for an A-B comparison.

I'm surprised that, with all his knowledge of the subject, 91buickman did not suggest it.

Norm

[88 Coupe]

andrewk wrote: ........ Personally, I don't think there can be that many like you out there ........
Of course there are. They are the ones who "talk the talk'' but are unable to "walk the walk".

We usually call them "ricers".

andrewk wrote: ........ your list of jury-rigged modifications ........
They would make for an interesting discussion. Maybe someone will start a new thread.

Norm

[andrewk]

Found this while browsing the internet tonite.

In response to 91parkave on 3800pro- when posting essentially the same thing as he did here...

jeep45328 from 3800pro.com wrote: You will have a cooler intake temp, you're not recycling hot exhaust gases into the tract. All out builds are about one thing and one thing only : torque (although where that torque comes into play obviously varies by the build). If you can take that volume of exhaust gases out and replace it with an A/F mixture, people will do it.

For a street vehicle, like I said, I just can't recommend it. I don't like paying more in fuel costs than I have to, and my experience is quite the opposite of yours when it comes to mileage. The reason why I mentioned timing - how many people do you know half ass things? I see quite a bit of it at work blocking off an EGR, and fueling with low test. Hmm....ping ping ping...knock sensor anybody?

[91parkave]

Quote:
[QUOTE="billboost37"]

BillBoost37
Moderator Bill Bostick
1997 SSEi
Join Date: Sep 2006
Location: CT
Posts: 390



What is your goal in removing it?

Intercooling, weight reduction, less intake dirt?

Being in an emission testing state myself where they pop the hood to verify the emissions equipment is there, I plan on programming mine out and that is all.

The decision on which way to go should be based on your needs. I understand most use block off plates for the exhaust and LIM holes with some sealant when removing the actual valve and piping.
http://www.3800pro.com/forum/general-tech/18432-removing-egr.html

PITA #1 can verify billboost being a expert on things from bonneville club, reading what he said, it goes right along with what ive said all along. Intake dirt. other members have said intake temps are lower as well, amongst other things i have said before.get rid of the EGR If your modding car for better performance reasons.dont get rid of Egr's in stock setups unless your anal about you intake being clean, then keep your EGR.

[88 Coupe]

andrewk wrote: Found this while browsing the internet ........
Interesting. I was reading the same thread. Here it is, in context.

in 3800.pro, jeep45238 wrote: 91buickman wrote: GET RID OF THE EGR ........ Why? When you mash on the throttle, it dumps in little to no exhaust gas. When you're not laying into it, it still only dumps a small amount in. Guess what? That inert gas lets you run a lower octane fuel without detonation or pinging. For a street car...why would you want to get less timing or pay more for fuel?

91buickman wrote: urban legend: i know how a EGR is supposed to work but real world app's prove otherwise IMO, to me gas mileage is better with it off, and if anything you have it backwards with timing, IME you will have less knock and cooler intake temps w/o a EGR, thats why NONE of the performance builds you see on various forums DONT run a EGR You will have a cooler intake temp, you're not recycling hot exhaust gases into the tract. All out builds are about one thing and one thing only : torque (although where that torque comes into play obviously varies by the build). If you can take that volume of exhaust gases out and replace it with an A/F mixture, people will do it.

For a street vehicle, like I said, I just can't recommend it. I don't like paying more in fuel costs than I have to, and my experience is quite the opposite of yours when it comes to mileage. The reason why I mentioned timing - how many people do you know half ass things? I see quite a bit of it at work blocking off an EGR, and fueling with low test. Hmm....ping ping ping...knock sensor anybody?
How dare he argue with 91buickman.

Norm

[88 Coupe]

91buickman wrote: DanGTP wrote: ........ wondering exactly what removing the EGR system entails ........ billboost37 wrote: What is your goal in removing it? ........ less expensive to remove the EGR than it is to replace it with a new one .........
The question related to removal, not consequences.

How does it relate to anything in this thread?

91buickman wrote: ........ billboost being a expert on things ........
Yes, he is knowledgeable about topics relating to Late Bonnevilles.

How does it relate to anything in this thread?

91buickman wrote: ........ reading what he said, it goes right along with what ive said all along ........
Not even remotely.

91buickman wrote: ........ other members have said .......
What other members, and under what circumstances?

91buickman wrote: ........ i have said before.get rid of the EGR ........
You have been saying a lot of things. Very little of it, has had any basis in fact.

How does it relate to anything in this thread?

Norm