I have an 86 Z28 w/LG4. What kinds of wiring problems will I run into if I swap in a vacuum controlled carb/distributor and get rid of the ECM? Will I have to mod the harness for the distributor? Will my electric fan and gages still work? I basically want to get rid of the 305 and go with a modified 350 or 383.

 

What you propose to do will work. By changing to the "older" vaccum controled distributor you will eliminate the need for the computer control of the distributor. You will not need to modify your wiring harness, just hook up the power wire just like the one you now have, then run a vaccum hose to the carb and you are done. AS far as the gauges are concerned, they should work without the computer as they are not controled by the computer, but by the sensors (oil, water,etc) just as any older cars are. Hope this helps.

 

You do realize that youre not going to gain any power by ditching the computer and all of its components. What you will accomplish is lost fuel economy, driveability and ability to pass emissions.