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Discussion Starter #1
I'm hoping you can answer a Corvette related question of mine or direct me to someone who may know the answer.
I own a Steel Blue Metallic 1975 L48 Corvette. I have the NCRS Technical Information Manual & Judging Guide. My confusion is about my Emissions / Tune up label located just above the hood latch on the drivers side reads AT, not WJ or AS as the manual says it should. I'm very positive it is the original label from the factory. My car is a semi-early production... was this label from a '74 .... Any insight or lead is very appreciated.
 

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According to the Doc Rebuild catalog, all the 74's had a 'Z' as the first character of the code. ZB,ZD,ZF,ZH,and ZJ. The Doc has no listing for a 'AT' for any model year.
 

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you might try ncrs.org for the technical discussion forum.
 

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Check the label again. There is probably a GM part # and a date in fine print along one of the edges.

:thumbsup:
 

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Discussion Starter #6
Here is a picture of my emissions label on my '75 Just in case the picture isn't clear enough, in the upper left corner it reads:
AT
350 - 400 CU. IN.
4 BBL Carb
CM11K43

In the very lower right corner along the bottom, it reads:
..............PT NO 360421

Does Anyone Know Why This Is AT ?

The NCRS manual says st the bottom of the 1975 and 1976 labels reads, "This vehicle conforms to U.S. EPA regulations applicable to 1975 (1976) model year new motor vehicles with the exception of the carbon monoxide standards for California" (75 part number 360422 & 76 part number 37258?) The upper left code for a 75 should be either WJ or AS according to the NCRS manual for my L48 part number 330560. If my car was (and it's not) and L82 WK or AU would be the upper left corner letters (not AT) part number 360422.

I know for certain that this emissions lable on my car is the one on the car from the factory. So, I am still wondering why my emissions lable is AT ? ? ?

 

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our 75 is an L82 and says AU in the upper left corner, however it also states 350 cubic inch, hi perf, 4 bbl. part #360422 is in the lower rite corner, i know that this is a different engine than you have, but hope it helps you somewhat, am curious as to what you discover!! good luck!!
 

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Discussion Starter #8
I just checked my Corvette America assembly manual. There isn't anything in it that shows the emissions label. I then went out and check my engines stamp pad. It has a CHZ code that the Corvette Black Book says is a California Emissions car. So, I'm wondering if the emissions labels were different on the CE cars? How would I find that out ? I love chasing this kind of stuff down.... honestly I think it's fun learning more about your car!
 

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from california to quincy illinois, i'll assume that your car is an automaic transmission?? i'm surprised that the ncrs hasn't addressed this for california emmisions, call the judging leader in your manual, i believe it's in the front, they are very helpful! keep us posted, am curious as to what you learn....
 

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Discussion Starter #10
ok, I went to docrebuilds website and looked for emission labels...
75 165 HP L-48 Federal 360420 AS 8999757
75 165 HP L-48 Calif. 366100 DR 8999776
75 205 HP L-82 360422 AU 8999758

The part number on my sticker is 360421. That part number is not mentioned in the 75-77 NCRS Technical Information Manual & Judging Guide.

Still no reason why my car reads AT....
I enjoy researching this stuff but now it's getting frustrating...

And then, I found this on the internet:
Automotive Recall and Technical Service Bulletin Titles for 1975 Chevrolet Corvette V8-350 VIN JT 4-bbl.

TSB Number & Issue Date TSB Title
75E01 OCT 75 Recall - Incorrect Emission Control Label
75E6 MAR 75 Recall - Vehicle Emission Control Label
75E02 JAN 75 Recall - Emission Control Label & Fuel Label Missing

(many other recalls listed)

http://www.alldatadiy.com/TSB/10/751006c1.html

... but, this doesn't tell me what the wrong one was... maybe I still have a label that didn't get changed from the recall ? ?

(you have to pay $ to get that info from them)


Yes, my car is an Automatic L48 (but I love it)!


I haven't been a member of NCRS for years.... not sure I will get any help if I'm not a current member...:D
 

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I haven't been a member of NCRS for years.... not sure I will get any help if I'm not a current member...:D
I'm current. Give me a day or two and I will scour their forums and get back.

steve
 

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Discussion Starter #12

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I found nothing on the NCRS forums but did find something intersting elsewhere: http://www.nastyz28.com/camaro/em-label.html look down the page to '75. It looks to me like your vette got a camaro emissions sticker. It may have other applications as well but at least you get the idea. Must've been a 'monday car' as they say.

steve.
 
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