i don't want to sound stupid, but i want to know what EGR really is. what is it and i was wondering if my EFI engine really needs it or can i just block it off and cut it out? and i was wondering if the air pipe that has 6 small tubes that goes into the head is part of the EGR system.

 

EGR stands for "exhaust gas recirculation".

If you look on your rear exhaust manifold, you will see a tube that runs up to an egr valve, thats connected to the back of your intake.

At cruise the egr opens up, allowing the exhaust gases to be reburnt in hopes of cleaner emissions, as well as introduced to cut down the amount of fuel required to operate, in hopes of improved mpg. You may wanna look at the post titled "do I need my egr", should see it near this one.

Those 6 tubes you see are "air injection", basically it introduces air into the exhaust in hopes of a cleaner emission out the tail pipe.

A web definition is as follows:

A system that injects air into the exhaust ports of the engine for combustion of unburned hydrocarbons in the exhaust gases, thus producing "cleaner" exhaust emissions.

And yes this is part of your emissions system.

I have used an EGR block off plate for years, I noticed no ill effects, your results may differ.

Also wanna point out, I did not do this in hopes of a power gain, I chose to delete the egr tube to make my header installation easier. If you have emissions testing, leave it be.

 

thanks a lot that explained a bunch.

 

I also think that because your engine runs leaner with the egr enabled it will also make "the already lean 300" very succeptible to vacuum leaks and the problems that it causes thereafter. Could be wrong, but would the egr disabled be harder on the catalytic converter? Things you have to look at. Also many posts talk about detonation problems associated with disabling the egr. Better idea ona carbed model than an EFI? I seems like the computer, all emmissions components and everything is calibrated around the air fuel mixture that runs best with proportions of NOX gasses etc. Id like to take all that junk off one day, no testing up here. I also concerned about emmisssions control, but really is it really making a difference anyway? At this point I don't think it really matters anyway!

I still burn less gas than all those power hungry high output V8s they make today, emissions controlled or not. And some of them have less displacement.

If you toast your rings, or just over time carbon builds up then you emmisons controls takes a beating, and eventually gets plugged anyway. Then everything goes downhill from there, that might just take a few miles off the motor too.

If you take the cat off, you can run on better quality oils like rotella than contain more minerals and stuff to protect the motor. The oils today are pretty much made to be easy on the catalytic converter; they contain less minerals and such.

 

I think "stoich" air fuel ratio is ideal for catalytic converter function, so I would say your on to something, however, I don't have one of those either so...


I have never heard of a detonation problem, due to blocking the egr on an efi engine. I think someone suggested or guessed it might be a possibly outcome, willing to listen though.

 

I am struggling with that question myself, and have done a lot of research on EGRs. I am still not sure they hurt you - but they can be a real pain to maintain.

I wrote my notes up here - http://www.old-fords.com/egr_system.htm

I would be interested in your comments/corrections.

 

Sorry about that but my egr isnt working like it should, i think its staying open at idle and with my vaccum leaks, the air fuel ratio causing some pinging, you can even hear it at idle but drowns away with engine noise. So if its better to disable the egr, then good. Id like to do that, but im looking at wrost case scenarios here. Is that the only reason that ford put that in the motor was because of emissions? In previous posts a few have said that you may require high octane fuel to prevent detonation or retard the timing right? Man high octane is sure expensive today. Egr, is supposidly also used to prevent combustion temperatures because it dilutes the air fuel ratio with non combustibles. This also prevents detonation right? So does disabling the egr support this theory, i dont know.

 

beatupford

Best I can offer you, mines been blocked off for a few years now, I use the cheapest fuel I can buy and have not heard so much as a ping. Your results may vary

 

If it were me, I would reword or remove the statement "returning unburnable exhaust gas".

I believe the idea is to reburn the exhaust gas. Also something to consider, with efi systems, what if the first three cylinders are less efficient, the egr only pulls in gases from the back three cylinders, effective?

Otherwise looks like its all there.

How do you like megasquirt?

 

I love the MegaSquirt, but do not have it installed yet. It looks to be high quality - a well engineered board with quality components. I have the code for it on my computer and have just started going through it.

I am a bit away from actually running it.

Thanks for the tip - it was your suggestion that clinched it for me.

 

Cool, interested in reading your thoughts once its installed.

 

[QUOTE=Motorhead351]If it were me, I would reword or remove the statement "returning unburnable exhaust gas".

I believe the idea is to reburn the exhaust gas.


Actually the idea is that the egr is introducing an "inert" gas. Exhaust just happens to be a handy, free and plentiful inert gas and that's why it is used. No reburn intended.

 

Sounds good to me.

http://www.fordscorpio.co.uk/egr.htm

 

Never dealt with a mega squirt system. I have with motec and performance electronics. the only thing i don't like about the mega squirt system is that it is a speed density system like the pre 93' f series. You can't run radical camshafts and make major modifications that would cause your vaccum to be irradic(sp)


"Best I can offer you, mines been blocked off for a few years now, I use the cheapest fuel I can buy and have not heard so much as a ping. Your results may vary"

I like your style did you have to buy any resistors to keep from getting the CE light?

 

NO, I left the harness connected to the sensor, otherwise I did have a CEL.

You mean 95 and earlier f series were speed density?

I believe some of the megasquirt users have played around with a mass air meter. Thanks goodness the old 300 doesn't need a radical cam to make decent HP.