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EGR- do I need it?

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Old Sep 10, 2009 | 07:07 PM
  #21  
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Originally Posted by fauxrs2
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
One again in the quoted post...It can be done. Having all smog equipment and still have a strong car.. In my above "RANT" so to speak. I was just......being me. If I ticked anyone off. I do apologize!!!. I just know that my hands are tied and I can't change anything...unless anyone wants to start a donation fund so when I get busted by the feds...I will have the bucks to pay for it. To all of you...do what you want....it appears you are going to do it anyway. And if you can get your numbers like the one above without any smog devices...than congrats.

Once again, sorry for the "hyperventilating".
"DUB"
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Old Sep 10, 2009 | 07:11 PM
  #22  
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Originally Posted by 73, Dark Blue 454
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.
Want to bet on that! I was in this group. The federal Environmental Protection Act says no alterations.

http://img.photobucket.com/albums/v1...mogarticle.jpg

Last edited by Paul L; Sep 10, 2009 at 07:14 PM.
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Old Sep 10, 2009 | 07:30 PM
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I had been having trouble with my car when I first bought it. It would run fine for about 30 minutes, but then would begin to ping. I found that the vacuum lines to the EGR were not routed properly. When I connected them correctly, the problem went away.It must have been put there for a reason. I'd say leave it on.
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Old Sep 10, 2009 | 11:04 PM
  #24  
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"And then I realized that if I had ten divisions of these types of men then our problems here would be over very quickly." -- Colonel Kurtz in Apocalypse Now
Originally Posted by grandmastercorvette
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"
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Old Sep 10, 2009 | 11:59 PM
  #25  
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Dude
Are there any feathers in you'r headress, And if so what tribe are you from ?
By the way did your grandparents or thier parents migrate to MY wonderful country and take land away from Indigenious people's .

True American
JRL

P.S. 6000,000 more that want to be here and are willing to fight our war's
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Old Sep 11, 2009 | 12:02 AM
  #26  
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Paul 74,..good artice but that's a Canadian issue, not the feds here in the colonies.

Also, here in Texas, any car over 25 years old is no longer required to undergo a sniff test or any other emissions inspections.

FWIW

Last edited by 73, Dark Blue 454; Sep 11, 2009 at 03:44 PM.
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Old Sep 11, 2009 | 12:21 AM
  #27  
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Originally Posted by jrl77
Dude
Are there any feathers in you'r headress, And if so what tribe are you from ?
By the way did your grandparents or thier parents migrate to MY wonderful country and take land away from Indigenious people's .

True American
JRL

P.S. 6000,000 more that want to be here and are willing to fight our war's
As a matter of fact, I am 1/2 Choctaw.
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Old Sep 11, 2009 | 07:30 AM
  #28  
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Originally Posted by fauxrs2
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
A couple of points about your comments above:

1. California is one of only of handful of states that insist that a car continue to meet the emissions requirement for the year it was manufactured. Most states have no emissions requirements for cars over 25 years old, as it should be.

2.An example of a heavily modified 78 corvette meeting emissions requirement is not what I referenced in my comments above. Citing a 78 corvette, passing emissions with all hardware and cats, with a basically new motor/rebuilt with aluminum heads, roller cam, etc is completely different that trying to pass emissions with a basically stock motor and OEM emissions hardware. Passing emissions requirements with all new engine components, updated to modern standards, is not comparable to passing emissions with a stock motor.

3. My 78 L-82 with no emissions recently just out of curiosity registered 850 PPM HC with ZERO emissions equipment when the Federal limit in 1978 was 800 PPM as a reference on a totally stock internals engine. In fact, there are numerous instances of cars from 1975 to the mid 80's passing emissions with no cats since the car manufacturers did not test every engine configuration to pass the Federal emissions but rather slapped on all the emissions equipment on every car without testing each one. Again, totally different scenario today!

The point is that often times for cars in the mid 70's to early 80's especially, if tuned correctly, these vehicles can pass an emissions test standard WITHOUT any of the so called equipment like a cat since the limits were so loose and the standards so high due to the poor technology to control emissions. Again, the point is that a properly tuned motor generally would meet or be close to the emissions standard 25 years ago WITHOUT all the garbage emissions equipment from that era!

Again, for cars that are over 25 years old and still on the road, this whole issue is totally ridiculous!

Last edited by jb78L-82; Sep 11, 2009 at 07:46 AM.
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Old Sep 11, 2009 | 08:09 AM
  #29  
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Originally Posted by 73, Dark Blue 454
Paul 74,..good artice but that's a Canadian issue, not the feds here in the colonies.

Also, here in Texas, any car over 25 years old is no longer is required to undergo a sniff test or any other emissions inspections.

FWIW
Just to clarify. We have emissions testing for newer vehicles (1988-on). That is a provincial (Ontario) program. The incident in the article (and there are others) involved a visual (not sniffer) inspection for cat con, EGR, PCV, etc. In other words factory-installed equipment. A charge was laid for absent devices under the federal Environmental Protection Act (Canada/EPA) which has no date provisions.

Perhaps matters are not as stringent in the USA. In fact they are not in some other Canadian provinces as the EPA is not as rigorously applied. Someone will correct me if I am wrong but I believe you have a federal version of the EPA. For example, muffler shops will often refuse to remove a cat con from a car so equipped and install true dual exhaust. The fine is fairly substantial.

My point is that such laws exist. Whether they are applied state-by-state, province-by-province seems a real mixed bag. And for good reason. Who in positions of authority have the training/competence? As an example with my car, the 1974 Corvette L-48 (non-California) with automatic transmission did not have an AIR pump. The L-48 with four-speed did. Strangely, the year before, all 1973 Corvettes had AIR pumps. There are so many permutations like this.

I appreciate the opportunity to comment.
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Old Sep 11, 2009 | 08:09 AM
  #30  
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Originally Posted by paul 74
Want to bet on that! I was in this group. The federal Environmental Protection Act says no alterations.

http://img.photobucket.com/albums/v1...mogarticle.jpg
Interesting article. Obviously, it was a revenue enhancement vs environment protection program.
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Old Sep 11, 2009 | 06:39 PM
  #31  
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Originally Posted by jb78L-82
A couple of points about your comments above:

1. California is one of only of handful of states that insist that a car continue to meet the emissions requirement for the year it was manufactured. Most states have no emissions requirements for cars over 25 years old, as it should be.
As it should be?... in your opinoin. With that type of thinking we only get worse pollution as much like it was in China during the Olympics when the government stopped people from using cars due to the air quality being so bad..because some countries would not attend unless they got the air to improve....or do you not remember that? I know that there are other issues that contribute to OUR dirty air...but I was just trying to make the point that why dont you TRY to DD your part. If you remove everything and blow clean numbers...than at least the results of your tune-up is not making an impact on our enviroment.


Originally Posted by jb78L-82
2.An example of a heavily modified 78 corvette meeting emissions requirement is not what I referenced in my comments above. Citing a 78 corvette, passing emissions with all hardware and cats, with a basically new motor/rebuilt with aluminum heads, roller cam, etc is completely different that trying to pass emissions with a basically stock motor and OEM emissions hardware. Passing emissions requirements with all new engine components, updated to modern standards, is not comparable to passing emissions with a stock motor.
No it may now be the same..but it shows that at least the owner is doing what is required to get an engine to pass strict emissions in his state. And if a stock engine in his state fails...then that is telling someone that it is time to "freshen things" up a bit and get it to pass or don't drive it.

Originally Posted by jb78L-82
3. My 78 L-82 with no emissions recently just out of curiosity registered 850 PPM HC with ZERO emissions equipment when the Federal limit in 1978 was 800 PPM as a reference on a totally stock internals engine. In fact, there are numerous instances of cars from 1975 to the mid 80's passing emissions with no cats since the car manufacturers did not test every engine configuration to pass the Federal emissions but rather slapped on all the emissions equipment on every car without testing each one. Again, totally different scenario today!
850 HC in my state is running too rich. The standard was 220 PPM HC.

And as for these "untested engines". I think that you are mistaken or you would have heard about all of these new cars back then that were failing emissions testing. And the stickers on the cars that stated that it conformed to the federal standards were all wrong.

Originally Posted by jb78L-82
The point is that often times for cars in the mid 70's to early 80's especially, if tuned correctly, these vehicles can pass an emissions test standard WITHOUT any of the so called equipment like a cat since the limits were so loose and the standards so high due to the poor technology to control emissions. Again, the point is that a properly tuned motor generally would meet or be close to the emissions standard 25 years ago WITHOUT all the garbage emissions equipment from that era!
Keywords: properly tuned. Which when many people remove equipment..they rarely have it tested. As long as it cranks and looks good they are happy... And if you get it tuned corrrectly and it has good emissions than ...once again...you are at least doing YOUR PART.

WE can all go round and round on this subject. WE all have our views...and we all are entitled to them...but the views of some of you are not in the BEST INTEREST of WE THE PEOPLE....and some of the views are in the best interests of us all. So to those of you who TRY to get your emissions correct... I applaude you...at least you are TRYING...and those of you who don't TRY.......all I can think of is that a winner never quits...and a quitter never wins.

I am NOT a NATIVE AMERICAN...but that still does not mean that I do not care about MY COUNTRY and OUR ENVIROMENT.

The best to ALL of you.
"DUB"
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Old Sep 11, 2009 | 07:07 PM
  #32  
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Grandmaster,

I enjoy your posts and tend to agree with you. Interesting reading. FWIW my 1974 now here in Canada came from CA with a replacement engine. It has a CARB certification. But I can tell you it is dirty on start-up before the TVS and EGR kicks in. And even after. I do not have one but the cat cons do a very nice job. I saw this on previous cars.
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Old Sep 11, 2009 | 07:10 PM
  #33  
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"850 HC in my state is running too rich. The standard was 220 PPM HC."

"And as for these "untested engines". I think that you are mistaken or you would have heard about all of these new cars back then that were failing emissions testing. And the stickers on the cars that stated that it conformed to the federal standards were all wrong".

All I am saying is that for my 78 L-82 that I drive 500 miles per year, the whole emissions issue is really a non issue, as it is probably for a host of other folks with 25 year old cars.

I think that you misunderstood my comment about the late 70's to early 80's cars that when some people removed hardware at that time such as a cat, many vehicles could pass the emissions standard without it, as many found out. At that time, GM did not test every engine configuration to pass the emissions standard, many cars just got the hardware. The limit in my state for model year 1978 is 800 PPM HC, not 220 HC. A stock 78 L-82 could not pass 220 HC limit unless it was running on 3 cylinders (a joke!) with the L-82 cam with all the overlap at idle, no way.

I am totally for retaining all emissions equipment on modern cars, as stated previously and which I have done on my other 3 late model cars, just not on vintage cars that will run much better without all the poorly designed emissions equipment, limited mostly by technology limitations from 25 years ago. Agree to disagree?

Last edited by jb78L-82; Sep 11, 2009 at 07:13 PM.
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Old Sep 12, 2009 | 10:24 AM
  #34  
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2.An example of a heavily modified 78 corvette meeting emissions requirement is not what I referenced in my comments above. Citing a 78 corvette, passing emissions with all hardware and cats, with a basically new motor/rebuilt with aluminum heads, roller cam, etc is completely different that trying to pass emissions with a basically stock motor and OEM emissions hardware. Passing emissions requirements with all new engine components, updated to modern standards, is not comparable to passing emissions with a stock motor.
A fair comment, so here are smog stats from when I was running the original L-82 - two different tests the 1st test was the 1st smog test the car had after moving to CA. from VA. I did no special prep, I just drove to the test station. It also set a good benchmark.

15mph HC(ppm) max=209 ave=57 meas=128
25mph HC(ppm) max=159 ave=45 meas=153

15mph co(%) max=1.25 ave=0.25 meas=0.00
25mph co(%) max=1.05 ave=0.19 meas=0.00

15mph NO(ppm) max=2425 ave=570 meas=822
25mph NO(ppm) max=2225 ave=648 meas=997


The second table is the results from my 10/17/2001 (2 years later)smog check, the only difference is the extra 25,628 miles on the car, and a new vs. the old original catalytic convertor.

15mph HC(ppm) max=191 ave=57 meas=92
25mph HC(ppm) max=159 ave=45 meas=75

15mph co(%) max=1.25 ave=0.25 meas=0.00
25mph co(%) max=1.05 ave=0.19 meas=0.00

15mph NO(ppm) max=1277 ave=570 meas=605
25mph NO(ppm) max=1137 ave=648 meas=510

There are some anomalies though, why did the max allowable change on several of the entries?, why did the rpm required to move at 15 mph and 25 mph differ so much, unless they did it in a different gear?

A stock 78 L-82 could not pass 220 HC limit unless it was running on 3 cylinders (a joke!) with the L-82 cam with all the overlap at idle, no way.
I did it twice once (just) on an original pancake cat - the 2nd time on a modern hi-flow cat

Note also that 850 hc is something like 4x what I am allowed. Its also interesting to note that the #'s between old and new are not all that different with the exception of HC's.

Last edited by fauxrs2; Sep 12, 2009 at 10:34 AM.
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Old Sep 12, 2009 | 11:22 AM
  #35  
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Paul 74,..good artice but that's a Canadian issue, not the feds here in the colonies.

Also, here in Texas, any car over 25 years old is no longer required to undergo a sniff test or any other emissions inspections.

FWIW
Last edited by 73, Dark Blue 454; Yesterday at 02:44 PM.
I don't believe laws are applied equally even within a single state. I live in Collin county TX (Dallas area) and we are close to as bad as Houston and LA with respect to air pollution. (Houston by the way is predominately caused by refineries.) Anyway, I do not need to pass the breathalyzer test as part of the annual 'safety' review, but I do need to pass the visual for all original smog equipment. It doesn't have to function, but it does have to exist and be mounted in the proper location.

That statement is true only to obtain a standard license. If I have antique plates, I am not required to undergo the annual safety review at all. Of course, I'm also not allowed to drive my car!
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Old Sep 12, 2009 | 12:34 PM
  #36  
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Originally Posted by Iskenderian




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
Actually California allows this. you must take the vehicle to a referee station where they will compare your emissions to the late model donor car, you will have to have the exact configuration as that donor car including OBD and the link under the dash. this also means you will need the donor computer .

If the car passes they affix a new emissions sticker and you effectively have to smog as whatever that modern donor car was.

I don't believe laws are applied equally even within a single state. I live in Collin county TX (Dallas area) and we are close to as bad as Houston and LA with respect to air pollution. (Houston by the way is predominately caused by refineries.) Anyway, I do not need to pass the breathalyzer test as part of the annual 'safety' review, but I do need to pass the visual for all original smog equipment. It doesn't have to function, but it does have to exist and be mounted in the proper location.
Its not that laws arent applied equally , its that the laws actually vary within the state. In California, despite what some think, there are counties where no tailpipe emissions testing is required, there are counties where only the idle test is required, and then there are enhanced emissions zones where the full gamut is required.

Last edited by fauxrs2; Sep 12, 2009 at 12:38 PM.
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Old Sep 12, 2009 | 12:35 PM
  #37  
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Originally Posted by fauxrs2
A fair comment, so here are smog stats from when I was running the original L-82 - two different tests the 1st test was the 1st smog test the car had after moving to CA. from VA. I did no special prep, I just drove to the test station. It also set a good benchmark.

15mph HC(ppm) max=209 ave=57 meas=128
25mph HC(ppm) max=159 ave=45 meas=153

15mph co(%) max=1.25 ave=0.25 meas=0.00
25mph co(%) max=1.05 ave=0.19 meas=0.00

15mph NO(ppm) max=2425 ave=570 meas=822
25mph NO(ppm) max=2225 ave=648 meas=997


The second table is the results from my 10/17/2001 (2 years later)smog check, the only difference is the extra 25,628 miles on the car, and a new vs. the old original catalytic convertor.

15mph HC(ppm) max=191 ave=57 meas=92
25mph HC(ppm) max=159 ave=45 meas=75

15mph co(%) max=1.25 ave=0.25 meas=0.00
25mph co(%) max=1.05 ave=0.19 meas=0.00

15mph NO(ppm) max=1277 ave=570 meas=605
25mph NO(ppm) max=1137 ave=648 meas=510

There are some anomalies though, why did the max allowable change on several of the entries?, why did the rpm required to move at 15 mph and 25 mph differ so much, unless they did it in a different gear?



I did it twice once (just) on an original pancake cat - the 2nd time on a modern hi-flow cat

Note also that 850 hc is something like 4x what I am allowed. Its also interesting to note that the #'s between old and new are not all that different with the exception of HC's.
I must say that those numbers for a stock 1978 L-82 are quite impressive with OEM emissions equipment. My car when I bought it in 1983 never could achieve those numbers. I am, also, a little puzzled about the HC limits you state. If the Federal limit for 1978 was 400 PPM (I stand corrected) in 1978, not by state, why is your limit in 2009 220PPM HC which it never was back in 1978. How can your limit be less in 2009 than it was in 1978? My 1994 Mustang GT 5.0 has 4 cats and fuel infection and it's limit is 220 PPM HC so I am confused how a 1978 corvette with a carb, L-82 no less, has the same limit for HC's?

Below from the Department of State are the Federal Limits:

TABLE 242.400-1 GASOLINE-POWERED MOTOR VEHICLE EXHAUST EMISSIONS STANDARDS
Maximum Emission
Concentration
Vehicle Class and Model HC (ppm) CO (percent)
Year
Class I:
Net weight or GVW of 6000
pounds or less
1975-1977 500 5.0
1978-1979 400 4.0
1980 300 3.0
1981 + 220 1.2

Interesting to note that with almost no change in the engines between a 1975 and 1980 corvette, the Federal emissions standards dropped from 500 PPM in 1975 to 300 PPM HC in 1980. Do I think that I could get my basically stock 1978 L-82 to a 400-500 PPM HC with OEM emissions, probably. 100-150 PPM HC, not likely, with a carb and the L-82 cam running a 180 thermostat (stock L-82's in 1978 ran 225+ degrees solely for emissions reasons-fact).

Last edited by jb78L-82; Sep 12, 2009 at 12:41 PM.
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Old Sep 12, 2009 | 12:42 PM
  #38  
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Originally Posted by jb78L-82
I must say that those numbers for a stock 1978 L-82 are quite impressive with OEM emissions equipment. My car when I bought it in 1983 never could achieve those numbers. I am, also, a little puzzled about the HC limits you state. If the Federal limit for 1978 was 400 PPM (I stand corrected) in 1978, not by state, why is your limit in 2009 220PPM HC which it never was back in 1978. How can your limit be less in 2009 than it was in 1978? My 1994 Mustang GT 5.0 has 4 cats and fuel infection and it's limit is 220 PPM HC so I am confused how a 1978 corvette with a carb, L-82 no less, has the same limit for HC's?

Below from the Department of State are the Federal Limits:

TABLE 242.400-1 GASOLINE-POWERED MOTOR VEHICLE EXHAUST EMISSIONS STANDARDS
Maximum Emission
Concentration
Vehicle Class and Model HC (ppm) CO (percent)
Year
Class I:
Net weight or GVW of 6000
pounds or less
1975-1977 500 5.0
1978-1979 400 4.0
1980 300 3.0
1981 + 220 1.2
I do not have any answers for you regarding the limits. All I can tell you is here in CA. and I have one of the sheets right here in front of me (the 12/22/06 test)- it reads quite clearly HC(ppm) MAX 191 @ 15 mph and 159 @ 25 mph.

Whats even more interesting is how these limits seem to be a moving target, note the massive difference on NO permitted between the two tests, perhaps this could be smog tech error I do not know. HC max in '06 was 191??? and its higher now? like I said, I cannot pretend to even explain it, but these are the numbers I have on the print outs that I still have.

I did find this on the Bureau of Automotive Repair website however

http://www.bar.ca.gov/80_BARResource...e-Jan_2007.pdf

Last edited by fauxrs2; Sep 12, 2009 at 12:55 PM.
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Old Sep 12, 2009 | 12:54 PM
  #39  
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From: Tennessee/Rhode Island
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Originally Posted by fauxrs2
I do not have any answers for you regarding the limits. All I can tell you is here in CA. and I have one of the sheets right here in front of me (the 12/22/06 test)- it reads quite clearly HC(ppm) MAX 191 @ 15 mph and 159 @ 25 mph.

Whats even more interesting is how these limits seem to be a moving target, note the massive difference on NO permitted between the two tests, perhaps this could be smog tech error I do not know. HC max in '06 was 191??? and its higher now? like I said, I cannot pretend to even explain it, but these are the numbers I have on the print outs that I still have
I appreciate your honest feedback on what's happening in your state with your car. At least I know that if I ever have to meet some kooky emissions standard on my 31 year old stock 1978 L-82 4 speed (no internal modfications) it can be done. As stated previously, I never would mess with the emissions equipment on a late model car, but on the L-82 vette for now, it is free of all that equipment and runs more like an early 70's LT-1 because of it. Thanx again.
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Old Sep 12, 2009 | 01:04 PM
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fauxrs2
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Joined: Feb 2005
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From: San diego ca
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Dont get me wrong, I would be deleriously happy if I didnt have to smog test this car, there are so many things I'd like to do to it that I am prevented from doing here in California but when I started building the new motor I decided I would see what I could do to build a strong motor that would still be smog legal.

An original L-82 is capable of passing California requirements, it better be in a darned good state of tune though
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