how mutch timing give the ecm at full advance on 350 non vortec .....from initial timing to full advance

 

is it the same has carburator engine ???

 

Basically same thing as carb you'd give the motor what it wants at WOT and everywhere in between...whether that be 30 deg or 36 deg or 38 deg...have to see what the motor wants

But you dont do it with the distributor...ecm has the tables that control spark timing and there you just adjust things.

But carb guys may set something like 18 deg initial at idle and have mechanical advance set to give 34 deg all in by 3000 rpm or something like that. They'd rev to 3000 and check with timing light til they saw 34 deg.

ECM control can do the same thing you just have to tell it what timing you want to run. I usually bring all my timing in by 2800-3000 depending on the setup. Mild motors only revving to 5500 or so I may have all timing in by 2800. My 383 revving over 6500-7000 rpm, with 3600 stall converter I had all timing in by 3200, just below peak stall point.

 

so if i raise up the rpm like on the carb motor should i see the full advance timing with the timing light .....motor seem to run pretty good with initial timing of 20 on the tab .....not sure what ecm put at 3000 rpm ..ill give it a shot and see thnx ...

 

the timing in neutral at 3,000rpm will be different than the timing during WOT at 3,000 rpm.


The most common "easy" way to dial the timing in is on a dyno. Start low and add timing bit by bit. An improvement will show up in the (torque curve, EGT) that is, torque will increase, the graph will get smoother, and EGT will generally drop. As you do this gradually your gains will halt, and that is your peak timing for those conditions, always pull it back a bit from that point for the extra hot day / bad tank of gas.

 

That might be possible with ECM controlled timing because it will adjust the timing based on engine load as it watches the knock sensor. For a basic mechanical controlled distributor, total timing will be the same with or without a load.