I just bought my first corvette, an 81 beauty....but the previous owner had removed the stock intake and put on a Edelbrock Intake with an EGR valve. I am having problems with my carb and my mechanic said I might want to invest in a new Edelbrock 650 cfm Carb, so after doing a little research I found one that matches up with my intake except the new carb is for engines without an EGR. If I put on an EGR block plate and disconnect the right vacuum hoses would I have any other problems or should I look at getting an intake for Non-EGR engines to match the carb.

 

The block plate and removing the vacuum lines is all you need to do.

Fixing the stock Q-Jet will cost as much and net you better drivability and more power potential, fwiw.

 

Your '81 is a computer-controlled car, and requires the use of a computer-compatible carb and distributor. If you follow your "mechanic's" advice, your car will permanently show an error code, unless you decide to really hack it up...

Lars

 

Norm, contact Lars and ship him your carb. It will come back to you as good or better than new. I listened to my mechanic years ago and went with an Edel Performer. They are ok carbs, not as good as a properly setup Qjet or Holley.

 

Lars doesn't work on E4ME carbs. If he was closer, I'd help him out with it. They're not too bad to work on, but definitely need to be live tested. Can't just rebuild one blind.

 

The intake is not the critical component here.

Don't know specifically about a Corvette computer carb application eg : tach signal etc.

But on similar vintage computer carbed vehicles if you have a suitable non computer donor car you can switch over the complete set-up : carb , distributor, EGR and all associated lines with no problem.

I have done it when the computer gave up the ghost in my daily driver 83 Malibu wagon - it runs way better than with the computerized carb.

And I had and made all the test harness' to set-up the computer carb after my previous rebuilds.
I also have the factory service bulletins etc etc .

I have come across and bought '81 Corvette set-ups at swap meets - probably computers went bad.

Without the proper test harness and test procedures often you have no way of knowing whether it's the carb or the computer - I had no error codes when the computer packed it in.

I had an extra carb which made no difference so switched to the non-computerized set-up.

Unplugged the engine light and drove on.

 

The State of Washington requires vehicle emissions testing in the major counties. You can't pass an emissions test without a functional "check engine" light, and you can't make that system work with a non-ECM carb and distributor.

Lars

 

No argument there - I'm in Ontario Canada ; ours only goes back 25 years.

Lars I will be contacting you (probably in the fall - off season ?) about doing up a '68 Q-Jet for me.

Which lends itself better to your "tuning" : an auto carb or a stick carb going on a mild 300hp 327 std trans application ?

jerry

 

Thanks Lars...all that is true but I live a long ways away from an emissions required county and also any vehicle 25 years old or older is exempt from that statute. With that being said, I appreciate all of the input and advice. I did find a Distributor that will work with the computer so that problem should be resolved, still looking for a carb but I may just stick with the old Rochester. I did find that my EGR Vacuum Control Solenoid was broken and locating a replacement is a bear of a problem....so I may be forced to go other route anyway.

 

new york state only goes back to the birth of OBD11...(1996) anything older is exempt from emissions testing. I was up in ontario two weeks ago for wine and beer tour... I saw more c3 vettes up there in one day than I see in 3 months in New York.

 

Emissions requirements or not - I don't think that the lack of local emissions inspections is a viable justification to hack up and destroy the electronic engine management system on a car. A well set up and restored '81 and '82 ECM-controlled Vette actually runs very nice. Why would anyone want to Bubba-hack the car instead of repairing it and setting it up the right way? If you don't want the ECM-controlled features, buy a '75 and deck it out to look like an '81. If I were looking to buy an '81, the destroyed ECM system and an Edelbrock carb would cut the value of the car by over 50%: Most metro regions require inspections, and these cars are seldom sold in small, regional areas. As soon as you eliminate the car's ability to be registered in most metropolitan areas, you have completely destroyed the value of the car for any future re-sale. (In the Metro Denver Area, that '81 Vette would have to pass the full visual and functional emissions test, including verification of the "check engine" circuit. The Vette being discussed in this thread could not be licensed in most counties in Colorado and in many other States, making it worthless if the discussed mods are made.)

Lars

 

Starting to think I was wrong to even ask the question.....as I have been told by many a person, "your car, you make it look and feel the way you want it to look and feel". I appreciate those who really love a beautiful restored automobile, they are indeed great. But in this instance, the car is not a stock car, the engine has been modified and many performance parts were added by the previous owners....I see myself finishing the product that they started. I could spend the money and restore to a factory classic but that's not me. These cars are indeed "sellable" out here in the sticks and since I just bought the car last month I see no immediate need to sell it. I fully intend to box up and store any stock parts I take off, replace what needs to be replaced and at some time in the future ..... maybe return it to a stock configutation if possible but for now I just want to enjoy the ride...

 

FWIW, the Q-Jet, E4ME or otherwise, will work just fine on your car, even with performance modifications. The E4ME is a little more sensitive to cam than a mechanical one.