I've got a 1980 with a GM crate motor, true dual (no cats) and an RV cam. The car runs great. I still have the EGR valve on the intake manifold along with the vacuum plumbing. Without cats, lowering the cylinder temperature isn't needed, and that's the main function of the EGR system. I'd like to get rid of it and have the engine look a little cleaner. I can pull the valve off and put a plate over the port. Can I plug the other intake manifold opening with a pipe plug? Carb would need to be plugged too. Any thought or comments on doing the EGR removal?

 

EGRs are good things and if they are operating properly don't impact on performance.......having said that my performer intake does not have the port for one so i am not using one.....yes you can plug it all up and be on your merry way with no ill consequences....

 

I see it as a harmless device. It does not require any horespower to operate and it benefits the environment.

If decluttering is a passion for you, then go for it. You may find that it pings without it because of those cylinder temps that you say are not a problem. A short drive on a hot day will answer that question.

It's kinda like a PCV valve IMHO. EGR and PCV are harmless devices if operating properly, and do lots more good than harm.

 

Like SanDiegoPaul says the EGR is harmless, but has nothing in common with the PCV. The EGR recirculates exhaust gas (some of your exhaust gas has unburned fuel in it) into your intake a high speed. If the EGR becomes defective you will suffer an iratic idle as you will be getting too much air for a good idle. The PCV vents your engine and prevents pressure build up. In the old days engines were vented to the atmosphere.

 

Won't running without an EGR "stink"? Unless the cockpit is airtight (HA! in our sharks), won't you smell the gasses inside the car?

 

Removing emissions equipment is against FEDERAL LAW. If people own cars that were equipped with emsiions equipment..then they should keep them correct. If you do not want emissions equipment on your engine...sell your car and go out and get one that did not come factory with that equipment. But many people THINK that the rules do not apply to them when they CHOOSE to change things to benefit them..either it be for looks or a few more horsepower. And like many use the few more ***** anyway on the street where you are already looking out so you don't get a ticket because you are in a Corvette.
Times are changing people...and the "powers" that be are changing things that just might make you wish you hadn't altered your car. If you remove any emission components...are you testing the exhaust to see how much crap you are adding to the air we ALL breathe...regardless if your state requires an emissions test? Chances are NO you are not. Once again...I guess the rules do not apply to those who feel that what they want is more improtant than the responsibility of doing their best to keep the emissions as low as possible. We want more, more, more and it is all about me, me, me.
"DUB"

 

Dude,

You forgot to begin your post with "Rant" and end with You are counter-productive to your cause/ideals.

Do you know that the OP's GM crate without EGR/AIR produces fewer emissions than the stock engine? My '80 stunck a lot more with the original engine with emissions controls than my GM crate engine does now without. I figure I did the environment a favor.

 

Is it correct that the EGR should be connected to 'Ported Vacuum'? PG.

 

Is this a real question?

 

Check your specific vacuum diagram. The EGR pintle, TVS sensor, and vacuum source are specific by year.

 

Is is also against FEDERAL law to illegally immigrate into this country. Last count, 6,000,000 and rising. They account for alot more smog than a couple weekend classic cars.

 

Simply stated, the EGR became the cure for retarded timing. When cars were detuned to reduce emissions,(retarded), this caused increses in cylinder combustion temperatures. The TVS senses the increased coolant temp, and injects "inert" exhaust gasses to lower the cylinder temps. Ergo, the EGR is not a smog device per say, but a cylinder temp reduction device. IF you have reset/recurved your timing to the power book specs of 36*, the EGR will never function, therefore it's removal will have ZERO effect.

 

...with your two last posts

 

Yes. It is non-functional at idle.

 

Let me start by saying that I would never recommend removing emissions equipment on later model cars that were designed with said equipment at the outset, create good power with the emissions equipment, and run well (good mileage) with emissions equipment installed. For example, my 1994 Mustang GT and 2001 Pontiac Grand Prix, both of which have been modified both have performance exhausts with cat (s) (four on the mustang GT), cold air intakes, etc and run great and make MUCH more power and are very clean from the exhaust (mustang GT just passed emissions with 9 PPM at idle and 2000 RPM's HC). My 78 L-82 on the other hand is a completely different story for many reasons:

1. All of the emissions equipment was NEVER designed at the outset for this engine. It was all added on to pass the Federal guidelines with little understanding of the effect on a pre emissions engine.

2. The car ran very poorly and extremely high temperature with the emissions equipment installed from the factory since the technology was in its infancy and poorly understood.

3. These engines run much better without emissions equipment and make MUCH more power with said equipment since the engines were never designed with this equipment in mind, as stated above.

4. Making Carb engines emissions compliant is an up hill battle which was finally achieved with the advent of electronic fuel injection and computers.

5. Most cars that are 20+ years old are rarely driven or driven for very few total miles annually and have zero effect on the overall auto emissions contribution when looked at in total-Regulating and holding these types of vehicles to an emissions requirement is total nonsense and ridiculous! Newer vehicles for the reasons stated above are different!

Finally, I would remove the EGR valve since any time you can freshen up the mixture for the engine to burn, the engine will run better, make more power, and run cooler, not diluting the incoming air mixture with unburned exhaust gases.

If someone feels strongly about mantaining the OEM emissions hardware on their car, by all means go save the earth but don't chastise those of us who are trying to make their vehicles better by removing equipment that hurt driveability, performance, mileage, etc on vehicles that are "hobby" cars for the most part. Get real!

 

My 78 with roller cam - aluminum heads - 10:1 CR and all the smog gear:

15mph HC(ppm) max=191 ave=47 meas=21
25mph HC(ppm) max=159 ave=37 meas=24

15mph co(%) max=1.25 ave=0.20 meas=0.01
25mph co(%) max=1.05 ave=0.17 meas=0.01

15mph NO(ppm) max=1277 ave=554 meas=570
25mph NO(ppm) max=1137 ave=468 meas=613

The motor is vastly more powerful than the original L-82 it had and smogs tons better than the L82 ever did

 

I think removing your PCV is a bad idea. If for whatever reason, I was getting fuel into my engine oil, I would like it if those vapors were actively vented and run through the business end of the engine. Off the top of my head, I can't think of a single downside to running a PCV system.

When it comes to EGR systems, I admit to not being an expert on their operation, but they never sat well with me. I retard my timing, giving me less time for a burn, my cylinders heat up, and my response is to add hot exhaust gases to the inlet mixture? Seems ariff with potential problems to me. I guess the engineers of the day worked through the problems, but it was just never something I thought was the best idea performance-wise.

I haven't taken any of the original smog equimpment off my car, so I don't take Grandmastercorvette's comments personally. However, when I passed emissions last year, my levels of CO and hydrocarbons were sufficiently low to pass year 2000 standards, this was with a carburetor that was not working well at the time. I am sure with the carb replacement I have completed this year and the additional work I spent tuning, I am even cleaner than that. There are a couple of points here. First, the state mandates that I get my emissions tested every two years, so in my case, the answer to the question:

is "yes". I'll be tested again in 11 months, and I am almost looking forward to it since I want to see if what I have done to the engine has lowered its emissions even further, I know it is running a lot better. Second, your post seems to imply that attempting to increase horsepower and striving to have the cleanest-running engine possible are mutually exclusive goals, when in fact, they are not. In fact, one facet of increasing horsepower in a given engine is tuning the engine to get the most complete burn possible in the cylinder, the result of suceeding in this regard IS a cleaner-running engine.

Additionally, when I got the car last year, it was getting around 7 miles to the gallon. My last two tanks of gas averaged 9.9 and 9.8 mpg, about a 40 percent improvement in fuel economy. Think how much less crap that will put into the air that we ALL breathe over the remaining life of my car. This is a result of doing my best to get the engine running as close to perfect as I can in order to maximize performance.

 

Wow. I'm glad I started this lively debate. My knowledge of the EGR system and its functions agree with the forum. My engine is well tuned (36 degree advance) and runs cool, so when I have time I'll dump the the remaining EGR components. Can the coolant temp sensor in the manifold be sealed with an NPT pipe plug?

As far as the environmental impact, the car currently meets all inspection requirements in New York. For a car that's over 25 years old, there aren't any smog gear requirements. That being said, it's a hobby car that gets driven under 2,500 miles a year (a real pity). My two garden tractors most likely pump out more NOx and CO2 annually than the vette. My newly installed TKO-500 gives me 25+ highway MPG's so I have reduced my carbon footprint considerably. My wife claims cleaning the garage floor would have a greater effect though.

 

I do have one thing to chime in on, the inflexibility of state laws. I converted my 1981 to run a late model LT1 EFI system from a 1994. While I have not had it sniffed yet, My guess is it is tons cleaner than stock. (running a brand new high flow cat too). but as the law is, that engine was never tested in that car soooo...... illegal.

-Bob

 

Grandmaster,..no need to hyperventilate here. I'm guessing 7 of 10 of your fellow forum members have removed some or all the pollution equipment . In fact, go to eBay and price used factory air pumps that we all removed back in the day and tossed in the garbage. Reason they're so expensive is because very few are left.

EGR? It effectively makes your 350 engine a 280~ CID engine at high vacuum conditions (cruise). At low vacuum conditions (passing another car, WOT, climbing a hill), it doesn't come into play.

As far as breaking laws, I'm guessing none of us will find our faces on wanted posters at the post office.