1G Ignition terminal

[DestinyAscension]

Hello fellow DSM'ers. Can someone pls explain to me how to set ignition timing CAS(1G N/A). Mine is set all the way clockwise(advanced) and engine works much better(It was in the middle before). The car struggles and blows black smoke when pushing acceleration pedal.
As far as I know - I need to ground the ignition terminal in order not to let ECU make any adjustments.
I suppose I need an adjustment and I've bought a timing light.

-Is it wrong to rotate CAS without grounding terminal? What's the difference and why it is wrong?
-Using a TMO Logger I see 5 degrees timing without any grounding? Can it really be any other ignition degree when TMO Logger shows 5 degrees?
-Setting timing with grounded terminal allows to set basic ignition which I can later adjust rotating CAS?
Thanks for the explanation in ADVANCE(hehe)!

 

[steve]

I assume this is for your Hyundai Elantra?

The point of the CAS is to sync the engine's mechanical timing with the ECU's electronic timing. Grounding the ECU input tells the ECU to not adjust the ignition timing and use 5 degrees BTDC while you adjust the sensor to match the crank timing mark.

With the CAS not in sync everything the ECU does is mismatched, ignition and injector timing. And anything reported by datalogging will be incorrect by the offset between mechanical timing and electronic timing.

 

[DestinyAscension]

I assume this is for your Hyundai Elantra?

The point of the CAS is to sync the engine's mechanical timing with the ECU's electronic timing. Grounding the ECU input tells the ECU to not adjust the ignition timing and use 5 degrees BTDC while you adjust the sensor to match the crank timing mark.

With the CAS not in sync everything the ECU does is mismatched, ignition and injector timing. And anything reported by datalogging will be incorrect by the offset between mechanical timing and electronic timing.

Sure it is, hah
Thanks for the explanation, Steve!