breather filter on egr

[mp3-79bronco]

well my mani doesn't have a fitting for the egr, and i cant find any fittings to even get welded on, so i'm looking for a way to cancel out the cel for the egr

i searched and found that some people are having success using a breather filter on the egr line...

i was wondering how many of you are doing this and are you having any problems?

 

[MSpeedFreak03]

from what i understand most of us just delet the EGR valve when we upgrade the intake manifold... i dont know what kind negatives consequences there are from doing it but im not an expert!

 

[magnumP5]

Personally, I believe that because the car came with and it set for an EGR system you should find a way to keep it. A lot of people swear this doesn't cause any problems but by adding a breather filter you will be allowing unmetered air into the engine. The EGR is also used as knock prevention by keeping combustion temperatures down. FWIW, I've switched to the 626 IM and I just got the corresponding EGR tube to go with it. When I upgrade again to a sheet metal intake manifold I will still be keeping my EGR. I say get a fitting welded on and use a corregated gas line as the EGR tube.

 

[MSP_4_CODY]

im running a breather filter, no problems so far!

 

[mp3-79bronco]

i cant find any fittings to use lol its the obx mani so i need a stainless steel fitting.. id like to keep it functional but ill do the filter if i cant... also the exhaust gas isnt metered

 

[magnumP5]

i cant find any fittings to use lol its the obx mani so i need a stainless steel fitting.. id like to keep it functional but ill do the filter if i cant... also the exhaust gas isnt metered

Look up what the EGR actually does before correcting people. Yes, exhaust gas isn't metered but your intake air most certainly is. The stock ECU's are tuned around the fact the EGR valve is present. The EGR recirculates exhaust gas back into the intake manifold to lower combustion temperature and to burn off some extra pollutants. The ECU is aware of this and thus is tuned appropriately. When you just put a breather filter on the pipe what happens when the valve opens? That's right, you let ambient air in - leaning out your air/fuel mixture and increasing combustion temperatures. The air is unmetered because it is entering the intake track post-MAF and therefore it is not considered when the ECU adds fuel.

All-in-all, these cars are meant to run with an EGR. There is little-to-no performance increase that would result of it either. It's just not worth it. Also, IIRC the fitting is a 1/2" NPT male fitting. It should be pretty easy to find one of those in SS.

 

[mp3-79bronco]

so i can just go to lowes and get a stainless steel 1/2 pipe and cut one end off and have it welded to the mani and use corrugated tubing to hook to the manifold?

 

[magnumP5]

1/2" NPT. You have to make sure it has the correct threading. If anything remove your EGR tube or go grab one from a junk yard and test it out.

 

[jamesk]

Personally, I believe that because the car came with and it set for an EGR system you should find a way to keep it. A lot of people swear this doesn't cause any problems but by adding a breather filter you will be allowing unmetered air into the engine. The EGR is also used as knock prevention by keeping combustion temperatures down. FWIW, I've switched to the 626 IM and I just got the corresponding EGR tube to go with it. When I upgrade again to a sheet metal intake manifold I will still be keeping my EGR. I say get a fitting welded on and use a corregated gas line as the EGR tube.

Id have to agree with Magnum.Putting a breather filter on egr is an easy way out of the problem, but it is not a fix.

The egr should be connected correctly, unless you remove the entire system and tune the ecu not to use it. Throwing a breather filter on just allows unmetered air into the system rather than the exhaust gases.

Thats not the right way to fix it.

 

[mp3-79bronco]

i really still dont see why it wont work right i mean you even said that the exhaust gas is unmetered, so when it opens the valve air is still going in just not hot air from the exhaust, and if its function was to cool, would not the colder air make it cool better? i just dont see why it would matter if the air came from the exhaust or outside? temp is the only difference i can think of between the two...

 

[magnumP5]

You're not following this. Exhaust is just that - the result of the chemical reaction of gasoline and air. Exhaust is not air, at least not if the engine is running rich or stoichiometrically (14.7:1 for gasoline). Exhaust gases are usually a combination of hydrocarbons (HC, unburned gasoline), carbon dioxide, carbon monoxide, nitrogen, nitrogen oxides (NOx gases), etc. Combustion processes are the hottest during stoichiometric reactions (ie 14.7 parts air to 1 part gasoline). By recirculating exhaust gases (not air) you're effectively richening the mixture by displacing intake air. This also serves to burn up some of those nasty exhaust gases I mentioned above from the previous process. Intake air temperature has little to do with the temperature of combustion.

However, the point you aren't getting is that the ECU was tuned to work with the EGR valve. It anticipates exhaust gases being recirculated, not extra ambient air entering from the engine bay.

There's just no good excuse for not running a true EGR line.

 

[mp3-79bronco]

okay i follow you now, thanks ill be sure to go look for a fitting and get it welded on

 

[MSpeedFreak03]

wow that really helped me understand the EGR process more... and thats why when i get my intake mani i will have the EGR tube with the new setup!

 

[mp3-79bronco]

does it matter if i hook the egr to the downpipe, or the manifold?

 

[magnumP5]

Shouldn't matter as long as it's not after a cat. Something tells me that i would be easier to have it running off the manifold (shorter tube) and that running it off the downpipe may interfere with turbo exhaust flow (you want this as fast and free flowing as possible).

 

[mp3-79bronco]

hey i just had a idea...since i have a 2.5 inch downpipe that goes into a 2.5 inch catless midpipe can i just get a adapter and use the blocked off o2 spot in my midpipe and go corrugated tubing from there to the egr? itd be a lot cleaner looking and is about the same distance

 

[magnumP5]

You could I suppose but that seems like an aweful lot of hose. I also don't know how the ECU will like that. The EGR CEL gets thrown when the EGR boost sensor does not detect a change in vacuum when the EGR valve is opened. Anyhow, why aren't you going to use that O2 sensor port? Wouldn't you want the first O2 sensor in the manifold, a wideband O2 sensor in the downpipe and then the second O2 sensor in the midpipe?

 

[Shadow102]

first off the EGR has absolutly ZERO to do with knock prevention. The EGR does not function at WOT or at idle and only at partial throttle during cruising speeds. Adding a little atmospheric air at light cruising speeds will not hurt the engine unless its unfiltered. Also an EGR does in fact meter air to a certain extent it knows when there is flow through it. On top of all this the ECU does compensate for what is ingested through the EGR. You forget there is a O2 sensor placed in the manifold that tells the ECU what the engine is ejecting and compensates accordingly. All exhaust is not created equal so the O2 still has to compensate whether its fresh air or exhaust air. All in all the only thing an EGR is good for is to cut down on NOx during light throttle/cruising speeds (ie what people drive at most of the time)...

The best way i have heard this put is you wouldnt stick a hose up your butt and plumb it to your nostril would you? why would you make your engine do the same.

 

[BlkWidow]

after reading this, now i have to find a welder to do my pipe hook up(bang).

 

[mp3-79bronco]

another benefit to me is that the midpipe is not stainless so i can just get a regular steel fitting and I can mig it on at school (we dont have a way to weld stainless) so id have to go somewhere for that...i can also put the nipple directly under it thus making the hose shorter than stock...

oh and my midpipe has the first o2 directly after the turbo, and the second at the bottom before it goes into the midpipe... there is no bung in the manifold