What controls the timing curve advance in the stock ignition system of 3rd Gens? Chiltons says that the ECM controls timing advance for all 3rd gens, is this accurate?


Does the MSD 6A control timing curve at all? or does it just add multiple sparks?

 

Yes, the ecm controls the spark curve. No, the MSD does not modify this. It only adds multiple sparks at lower RPM's, at higher RPM's there is no more multiple sparks, just a single one.

 

Is it possible to put a regular distributor in a 3rd gen with an aftermarket carb?

I mean, other than a possible check engine light, are there any consequences to taking the computer out of the loop?



Edit: This is an '86 Camaro originally carb-ed and there are no emissions tests here.

 

ecm controls timing curve of the distributor and the a/f ratio of the carb, if you swap one the other has to go too unless your aftermarket carb is a computer controlled quadra****...if your going to an aftermarket non-cc carb, get a non-cc hei distributor with vaccuum advance out of a late 70's early 80's (i think 76-82) gm car, i got mine at the junkyard for $15, make sure the end of the shaft doesn't wobble (up and down movement is ok, side to side is bad), it's a simple swap, you really might as well remove the ecm as a whole if your going to go ahead and change out the carb and dist.

changing the dist. out is simple, unplug the old one, note pos. of the rotor, spin new dist.'s rotor to point in the same direction, drop it in, connect the pink brown green and purple (i think those are the 4) wires back to the dist. (they connect the same to the new as they did the old) and reset your timing.