). 
What is EGR "high performance"?
Thread Starter
Instructor
Joined: Jul 2013
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From: San Francisco California
What is EGR "high performance"?
In searching for a new EGR for my 76' L48 with manual transmission. I came across 3 options:
1. EGR with special high performance
2. EGR with California Emissions
3. EGR W/O High performance with Cal Emissions
What are the differences here? They look identical in all the product images online at Corvette America. Passing SMOG in CA will be required but how does a tech know which is which and which one gives best fuel savings and performance for L48 California car?
Thanks
1. EGR with special high performance
2. EGR with California Emissions
3. EGR W/O High performance with Cal Emissions
What are the differences here? They look identical in all the product images online at Corvette America. Passing SMOG in CA will be required but how does a tech know which is which and which one gives best fuel savings and performance for L48 California car?
Thanks
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From: Southbound
Cruise-In II Veteran
Thread Starter
Instructor
Joined: Jul 2013
Posts: 119
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From: San Francisco California
After searching on Ecklers, Covette Central and such I can only find:
1976 L48 California with Automatic transmission (not 4-spd) What's the difference? There is a 1976 4spd with high performance that might work, but not sure if it's smog legal. Does anyone actually have OEM numbers on top of the EGR shown in the product images that states it's california?
Thanks
1976 L48 California with Automatic transmission (not 4-spd) What's the difference? There is a 1976 4spd with high performance that might work, but not sure if it's smog legal. Does anyone actually have OEM numbers on top of the EGR shown in the product images that states it's california?
Thanks
Race Director
Joined: Jan 2000
Posts: 12,399
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From: San Jose CA
After searching on Ecklers, Covette Central and such I can only find:
1976 L48 California with Automatic transmission (not 4-spd) What's the difference? There is a 1976 4spd with high performance that might work, but not sure if it's smog legal. Does anyone actually have OEM numbers on top of the EGR shown in the product images that states it's california?
Thanks
1976 L48 California with Automatic transmission (not 4-spd) What's the difference? There is a 1976 4spd with high performance that might work, but not sure if it's smog legal. Does anyone actually have OEM numbers on top of the EGR shown in the product images that states it's california?
Thanks
Thread Starter
Instructor
Joined: Jul 2013
Posts: 119
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From: San Francisco California
At the hair-splitting level, #2 could be the WRONG part depending on which engine his car was equipped with. But I posit that it doesn't matter horribly much...
Some manufacturers provide OE numbers on top, some expect you to write in the OE number on top. Every smog tech I've worked with does a visual (is it there with hoses in the right spot?) and functional check. The functional check includes manually engaging the EGR valve (either with a vacuum pump or by lifting the diaphragm by hand) and the tailpipe test. If the EGR is too far out of whack, NOx will be high.
Some manufacturers provide OE numbers on top, some expect you to write in the OE number on top. Every smog tech I've worked with does a visual (is it there with hoses in the right spot?) and functional check. The functional check includes manually engaging the EGR valve (either with a vacuum pump or by lifting the diaphragm by hand) and the tailpipe test. If the EGR is too far out of whack, NOx will be high.
Thanks so much.
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Race Director
Joined: Jan 2000
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From: San Jose CA
Great! I still have a functional problem with getting the correct EGR valve for the 76 L48 with manual trans and California. I can't find anywhere a "manual trans" version of the California EGR only the automatic. What really is the difference between a manual vs. auto egr? Can I use the Auto and function correctly?
Thanks so much.
Thanks so much.
Thread Starter
Instructor
Joined: Jul 2013
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From: San Francisco California
[QUOTE=Shark Racer;1590044530]Are you sure your car is a CA car? Only federal cars received a manual transmission in 1976. CA cars were L-48 only and added AIR typically.
No I am not sure. I started a thread some time ago about how to tell if it's federal or CA since I bought it at an auction in Ca with the block vin planed off and no smog equipment on it period. The emissions label long gone too. I contacted the REF and they said it was successfully smogged in 2010 but couldn't tell me if it stated federal or ca.
Honest opinion........... Should I just get the federal label and put those components in and forget about the AIR system? This would save me lots of time and money.
You may just have saved my build.
Any other thing u can think of that could prove its a federal car?
Thanks
No I am not sure. I started a thread some time ago about how to tell if it's federal or CA since I bought it at an auction in Ca with the block vin planed off and no smog equipment on it period. The emissions label long gone too. I contacted the REF and they said it was successfully smogged in 2010 but couldn't tell me if it stated federal or ca.
Honest opinion........... Should I just get the federal label and put those components in and forget about the AIR system? This would save me lots of time and money.
You may just have saved my build.
Any other thing u can think of that could prove its a federal car?
Thanks
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
No I am not sure. I started a thread some time ago about how to tell if it's federal or CA since I bought it at an auction in Ca with the block vin planed off and no smog equipment on it period. The emissions label long gone too. I contacted the REF and they said it was successfully smogged in 2010 but couldn't tell me if it stated federal or ca.
Honest opinion........... Should I just get the federal label and put those components in and forget about the AIR system? This would save me lots of time and money.
You may just have saved my build.
Any other thing u can think of that could prove its a federal car?
Thanks
Honest opinion........... Should I just get the federal label and put those components in and forget about the AIR system? This would save me lots of time and money.
You may just have saved my build.
Any other thing u can think of that could prove its a federal car?
Thanks
Honestly, though - if you have a manual transmission and a welded-in crossmember, it's not a CA car - you have a federal car. L-48 or L-82 is another question, the VIN would tell you that.
HTH.
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Instructor
Joined: Jul 2013
Posts: 119
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From: San Francisco California
If it still has the original carb, that would tell you. You can also get the original dealer invoice from GM and that will tell you if it was ordered with the California emissions package.
Honestly, though - if you have a manual transmission and a welded-in crossmember, it's not a CA car - you have a federal car. L-48 or L-82 is another question, the VIN would tell you that.
HTH.
Honestly, though - if you have a manual transmission and a welded-in crossmember, it's not a CA car - you have a federal car. L-48 or L-82 is another question, the VIN would tell you that.
HTH.
I have the AIM build book and was originally looking at the L-48 with AIR system install page. The only other page is the L-82 option that has an EGR but not AIR system shown. Is the L-48 emissions federal the same configuration as the L-82? I can't seem to find the diagram with components. There is a forum thread here that talks about federal components that I'll review.
As far as I'm concerned you have REALLY helped me out here and think I will go with the L-48 federal install realizing that if I have to go AIR after inspection, I will to get passed SMOG.
Thanks so much HTH
J