So I failed..............Emissions

[80Vette]

Took the 1980 Vette to the DEQ and FAILED!

The motor has only 2300 miles on a new engine. It does have a 3/4 cam but that's about it for mods.
All the emissions are on there (catalytics etc, PCV etc) but I had high (HC) readings. HC readings are supposed to be 220 but my car ran a 378. D@MN! The stupic car gets much better gas mileage than our new Durango

So, any advice from you Portland OR Vette drivers with a C-3 era Vette, forced to play (new car standards) in an (old car technology)???

Perhaps a re-jetting of the carbs, tune-up kit plugs/wires/rotor, vacuum leak somewhere??


Agggggggggggggghhhhhhhhhhhhhhhhhhhhh


Andy

 

[82ColEd]

That stinks !

I dont have any experience with this particular issue, but i did a search here and found this thread:
http://www.corvetteactioncenter.com/forums/showthread.php?t=5932&highlight=HC+readings

Someone more knowledgable will come by and give you a hand..


Hope it helps!

-Stefan

 

[80Vette]

Thanks Stephan!

Appreciate that!


Andy

 

[GerryLP]

Took the 1980 Vette to the DEQ and FAILED!

...
All the emissions are on there (catalytics etc, PCV etc) but I had high (HC) readings...Agggggggggggggghhhhhhhhhhhhhhhhhhhhh
Andy

And they didn't check the engine vitals for you? ad

If your timing is higher than at the factory setting, then your HC's could climb.

For example, I recently communicated with Lars Grimsrud, a very knowledgeable Corvette "guru" who has posted on the web some papers on automotive stuff, on a timing question for my L81.

He hinted that if I were to alter the initial timing on my L81-based distributor, then I could see a measure of improvement on performance for the L81 (in the + direction), but that the drawback would be that I could also see a climb on hydrocarbons.

Now, here in New Mexico we have those emission testing places that is about as big as single car garage in size, and all they do is tell you if you pass or not. I would not let those types of business make any adjustments on my car (even though they are very convenient for satisfying the requirements if need be), but if it is a regular shop, the they should have investigated what the probable causes are.

GerryLP:cool

 

[80Vette]

Thanks for the valuable input Gary, you see...here in Oregon, if you don't drive a Volvo wagon burning Bio-Diesel or drive a Subaru wagon, you're viewed as some type of knuckle dragging, un-enlightened neanderthal.
Any older, American V8 is considered a war monger. Not kidding either. This place is brutal for a Vette owner (C4 and older).

I've sent it to the Vette shop here in Portland and have found out that the carb was bad & had been tampered with. So, we're going to put in Edelbrock hi-rise performer manifold & a new edelbrock carb set-up. It has been guaranteed to pass.

So, silver lining, the car will be getting 15 to 10 more HP


Andy