Thread: Timing mode?

In EVERY case you want to sync the timing at the crank pulley with a timing light with what you have commanding in the software.

This is what the "SET TIMING" mode does.. this way what you are requesting in the tune is actually what you are getting at the engine!

For example, if you have you "SET TIMING" at 15*, you want to get your timing light out and set the timing at the crank pulley to 15* by moving the dizzy.

So when the ECU is commanding a timing value it is actually running it at the engine!

Thanks for clearing that up, John. Not that I would ever try this, but I'm just spit balling...

Would there be any difference in advancing the timing 2* to 17* on a stock ECU (in which case the ECU would think you were at 15*) and using a timing light to get to 15* and then retarding the expected timing on the tune? I fail to see how this would be much different than the first case. In both instances the timing set with a light is 2* off from what the ECU is expecting.

I'm in no way suggesting that you're wrong about this, just trying to understand what that difference would be.... It's all about learning here, right?

If you used a timing light to get 15* and then retarded 2 degrees from the tune.. then you would be 4 degrees retarded from your first example.

if you used a timing light to get 15* and then advanced 2 degrees in the tune .. then you would be equal to the first example for your ignition table.

It is all relative to what you are seeing or expecting from the ECU .. you can set it up however you would like.

If you set it to 17* while in set timing mode with the ECU commanding 15*, you will obviously be advanced 2* over what the ECU is commanding in the entire tune.

Moral of the story is just set your dizzy timing to the same value you are commanding in set timing mode. This way everything matches up and your tune can easily be ported and/or compared to other tune files.

Understood... Thanks for clearing it up.

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Is that counted left to right or right to left?

I replied to an email today with the following writeup and thought I would also post it here:

To set the timing, make sure the engine is fully warmed up (ECT Trim is 0), go to the SETUP tab, EXTRAS, DIAGNOSTICS screen, set the "BASE IDLE IGNITION" to match the "TPS CLOSED TIMING TABLE" value at the current idle RPM, and then enable "Set Idle/Timing Mode". If the idle rpm changes, adjust the IACV idle speed screw to bring idle rpm back to the value from the "Base Target Idle RPM" table at the current ECT. Using a timing light, adjust the timing by turning the distributor/CAS so the timing matches the "BASE IDLE IGNITION" value. If the idle rpm changes, again adjust the IACV idle speed screw. Verify the timing with the timing light again and make any necessary adjustment. Continue this process until the timing matches the "BASE IDLE IGNITION" value and idle speed matches the value from the "Base Target Idle RPM" table at the current ECT. Disable "Set Idle/Timing Mode" and your done!

Cheers,
Dave