Thread: remove emission controls

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I am removing all emission controls from my 1981 corvette it has the electronic q- jet carb and computer controlled distribtor. can i replace the distributor with a msd unit and leave the carb for now? I will eventually replace the intake and carb, but this a hobby car so I have to do it as funds are available.

Watch out, it is a violation of Federal Law to remove the emissions controls for a street-driven vehicle.

Given that, does your distributor have wires going to the distributor body (not the cap)? I'm not sure that the 81 Corvettes had "computer controlled" HEI distributors. If they are computer controlled, there is a separate connector that has wires that go thru the distributor body just below the cap lip.

The GM HEI is a very good distributor for street use under 6000 rpm or so. You can get lots of improvement parts for it, if the engine is relatively stock, changing it will not help performance.

yes it has the wires going thru the body of the dist. just wanted to know if I could do the distributor first and the carb later? the car has a nitrous set up so the extra spark power will be needed

Do you have a factory shop manual with a wiring diagram? I am not sure about the Corvette but the ESC in trucks the first years could be jumpered to disable the spark control (I believe that it was a retard function). Your wiring diagram should show that the distributor functions independently of everything except the knock sensor........unplugging the spark control wont work.

In 1981, this stuff was pretty crude so they didnt have everything integrated together.

You might want to consider these guys for your HEI, they'll curve it to exactly fit your specific needs.....
http://www.performancedistributors.com/gmssdui.htm

yes I do have a manual I have been a ford
tech for 30 years, this is my first chevy. as long as the spark advance has nothing to do with the computer controlled q-jet I think I will be fine. I plan on going with a MSD ready to run dist with vacuum and mechanical advance(no computer needed)
thanks. and if anyone needs ford advise ask away

If memory serves...If you unhook the ESC from the distributor the actuator inside the card WILL stop working and go to full rich....

You can jumper the distributor to work...On the 4 wire harness you hook the first and the third wire together ( brown and green) this bypasses the ecu....

just check the carb after you rplace the distributor...the actuator moves the metering rods up and down several times a second...you should be able to feel this.