Overload tables questions!!!

[torquemaniac]

I have some questions in respect to the Overload tables on the gen 2 CX-7...

I was playing with ignition timing in the Normal table, and noticed that none of the changes I made were effective when logging

Decided to also change the ignition timing Overload table, and then the changes were effective

After going through all the Absolute limits and Ignition tables, I found one odd thing : the Load limit force spark retard table is set at 0 everywhere...this table contain the load threshold for triggering an overlaod condition

Does this really mean that an overload condition is always set (because of the 0) and that the ECU use the Overlaod timing tables at all time?

As a side note, the Overload timing tables have less advance (and more retard) than the Normal tables

On top of this, there is an Overload retard table...are the values in this table added to the Overload timing table?

Attached are screenshot of the Load limit force spark retard and Overlaod retard table
Hope some of the top guns here can help out

[mituc]

I think that tune works exactly how you described it, permanently in overload.

On my tune the default overload table has the load limit set to 2.5 in all cells. This is the default. Probably you could set it to similar values so that you can benefit from using the normal tables which have more predictable variations based on the other tables they interact with.

[torquemaniac]

Thanks for the answer Mituc...I was actually refering to you when I said :''top gun''

Do you think the Overlaod retard is added on top of the Ignition Overlaod table?

Do you mind if I contact you directly for my tuning questions (I would pm you on MSF)?

[mituc]

The overload retard timing should be applied to the overload timing table as far as I know. Of course, on top of these the no knock high BAT/ECT table should also be in effect depending on where you are with the BATs or ECTs.

You can contact me any time you want, I just hope I will be able to help you.

[Steve @ VersaTune]

After years of looking at multiple implementations of this engine, I believe this is a High/Low Octane accommodation in the tune. They are tuning the CX-7 in many markets for low octane. By setting the "Overload" threshold in the Load limit force spark retard table, they determine whether the ECU should expect low octane fuel or not. It appears to determine which set of tables are used - Normal or Overload.