81' ecm

[94conv.]

Does anyone know what all the ecm in the 81 controls? I would like to change the carberator to a regular one and get rid of all of the smog stuff and change the exhaust over to ones without the air tubes. would this be easy and/or possible?

 

[black_81_vette]

The ecm dont do much.Best deal is go get a 80 down HEI dist ,and a pre feedback carb and your done.I did this to my 81 and it runs good.Oh and BTW you will have to disconect the ecm connection to the air pump and pull the belt off the pump.

 

[LanceB]

Not sure if my smog equipment is hooked up or not. Any horsey gain by disconnecting it? Where exactly is this pump? Thanks.

 

[81 Corvette]

the computer controls the timing on teh distributor, the carb, the smog equipment and the converter lock up on auto's

i swapped carbs, and distributors and removed the smog and all runs well

 

[94conv.]

how did you block off the air tube on the exhaust and mine is an auto so what do I do about the lock up on the converter?

the computer controls the timing on teh distributor, the carb, the smog equipment and the converter lock up on auto's

i swapped carbs, and distributors and removed the smog and all runs well

 

[94conv.]

also what about the tach drive on 81's and switching distributors?

 

[JohnZ]

No tach drives on Corvette distributors after 1974.

 

[81 Corvette]

air tubes. i just stuck a cork in the drivers side hose, and on the passenger side, ran the hose from teh exaust to the tube going to the cat. eventually, i replaced the exaust manifolds with headers.

the converter is controlled by the computer and locks it up at 45 mph. the sensor for this is in the dash somewhere and is not effected by removing the stock distributor or anything else.

the 81 uses an hei distributor that has two wires connected. one is the wire for firing the plugs, the other is for the tach. your new distributor should connect right up, mine did, and the tach works fine.

 

[Rudzvetz]

The tach is electronic and part of the distributor, same as every other HEI since 75'. The converter lockup will not work without the ECM unless you get the vacuum lockup setup off of an 80' vette or go with an aftermarket lockup kit. The speed sensor for converter lockup is part of the speedometer, but the signal to lock the converter comes from the ECM.


-Justin