Trashing the EGR?

[Shelly Harris]

So as not to extend the "throw away your timing light thread", I have started this one to open discussion on EGR valves. Barry experienced a dramatic loss of vacuum as a result of a stuck EGR valve which caused gasket failures.

Here's what is commonly accepted about EGR valves which were unheard of till the early 1970's

"The EGR valve helps your car more efficiently and completely burn fuel by recirculating a portion of your exhaust and running it through the combustion process again. This results in a cooler, more complete burn of the fuel which decreases you car's noxious emissions by prohibiting the formation of some harmful gases."

Do you buy that? Is it necessary and advantageous?

I ask because I am bringing a Mark IV 460 cid back to daily driver status and seriously considering trashing the ERG and all the hoses venting portions of the engine back up thru the air filter.

[Barry Wolk]

If your car still has the cats, I'd leave everything as is, but that's me. Everything works as a system which may be disrupted if one element is defeated. It was under $75 in parts to replace the EGR valve and gaskets.

Keep in mind, Shelly that the original carb, which I'm keeping, was designed around exhaust gasses entering the flow. I understand your desire to replace the crappy carb of the era, so eliminating the EGR at the same time may make some sense for you.

[Mad Scientist]

The EGR, smog pumps, retarded timing where all bandages that Detroit but on the engines prior to EFI to meet smog specs. Unfortunately all of these degraded performance and economy.

Personally I would get rid of all of them as they were known to cause problems like Barry experienced. Now obviously the engine will not run quite as clean as before. But on the other hand it probably won’t be as bad as some might expect because you should now get better gas mileage and with better mileage you will use burn less gas to go the same distance thus less pollution.

[Barry Wolk]

Not exactly.:rolleyes:

[Shawn Newcomb]

How does introducing hot exhaust gas into the fuel/air mixture result in a cooler burn during combustion?

[Don Henschel]

How strict are your vehicle emissions regulations in your location? Some larger cities have manditory testing. Some of us may have to leave that crap on.

[Mad Scientist]

In our area only 95 (98?) cars are now checked and this is done by just plugging into the on-board computer and looking for error codes.

Surprisingly I think they realized that there were not enough old cars running around to make any significant difference in air quality. Plus it costs more to do an IM240 test then just simply reading the cars computer for error codes.;)

[Shelly Harris]

Mad is right. IL finally exempted the older collector cars from testing. We used to use the "show car" exemption, but then you had to show insurance coverage which only covered you coming and going to shows. So I can tear out the EGR w/o worry of testing. So you think that stuff is crap?

[Shelly Harris]

How does introducing hot exhaust gas into the fuel/air mixture result in a cooler burn during combustion?

I picked that quote somewhere off a google search....

[Mad Scientist]

Not exactly.:rolleyes:

All other things being equal, if you were able to double the mileage of your car. Then if you traveled the same distance as before but now by burning only half the amount of fuel would you not produce only half the amount of pollution?

[Barry Wolk]

Double? You're dreaming. My '77 gets 14mpg with all the "crap". No Lincoln has ever gotten 28 mpg, so your logic is specious, at best.

All you're doing is justification for something you want to do, not something that's necessary.

[Mad Scientist]

You’re missing the point obviously your Lincoln will not get double its mileage short of costing down a mountain. But if you could somehow “magically” double is mileage or any other car that would have the effect cutting its pollution in half.
Thus anything you can do to improve mileage will reduce pollution. Now will it be enough to counteract the changes needed to produce it, that's the question?

The justification getting rid of these early smog devices is simple, the engine will have more power, have better drive ability and better economy.
This was proven early-on when these devices were first introduced. People who bought a new car with essentially the same engine complained to the dealers about the lack of performance. Many dealers would then re-tune the cars to the previous year’s specs. This made the owners happy and at the same time the environmentalists unhappy. So laws were then passed making it illegal for dealers to tune to other then the factory specs for that particular year. This of course did not stop the individual from tuning his car anyway he pleased, so more laws were pasted requiring that all cars must be tested once a year. The result of this was that many cars were tuned twice a year. Once just before going for the smog test and then once right after the smog test to make it run decently for the rest of the year.

But now with the advent of EFI all this is no longer needed. We now have engines with way better all round drive ability, performance, and economy. Assuming all the little sensors keep working correctly.:)

[Barry Wolk]

I get it. I happen to care what my car spews, and you don't. That much is clear. I have never defeated the pollution controls on any of my cars, and I'm not about to start now.

We clearly see things differently yet I don't seem to have to justify my views.

Just my $.02

[Roger Zimmermann]

My understanding is that the EGR valve is reducing the NOX by reducing the combustion temperature. The way it was sold to the public is misleading.

[Barry Wolk]

How was it sold to the public?

[Roger Zimmermann]

How was it sold to the public?
With that:
"The EGR valve helps your car more efficiently and completely burn fuel by recirculating a portion of your exhaust and running it through the combustion process again. This results in a cooler, more complete burn of the fuel which decreases you car's noxious emissions by prohibiting the formation of some harmful gases."