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Question for the '81 owners.



First let me introduce myself. My names Matt. I have a 1980 California Corvette with the LG4 305 with the computer controlled emissions stuff installed.

My question is what is the emissions system in a 1981 Corvette called? The '80 has a "C4" emission system. That's the name of the system, not referring to 84-96 Vettes. I'm wanting to install a 350 in my car and wanted to see if a PROM from the 81's could be used in my 80. I need to keep my emissions intact for emissions testing in my area.

Thanks for the help,
Actually it's the C3 system. Computer Command Control. Only oldsmobiles used C4. All chevy's 80 - 86 with carbs used the C3, but the 80 model is an oddball. To use the '81 you will have to change the entire system including the carb and distributor. On the other hand you shouldn't have any problems using the old system on a 350. I have done this swap many times without any problems.
Nice to hear that I can use the original chip! That makes my day a lot better.

In my shop manual it refers to it as the "C4" system though. That's throughout the entire manual and also I saw a few other web resources on my goofy system that agreed on that info.

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