Thread: Timing Maps..and Beyond!

Does anyone know what happens when you overrun your TP load to the far edges of the timing map in regards to the ECU and controlling timing? Does the ECU continue to retard timing based off the pattern before it or does it only accept the last timing value at the last TP load.

For example, let's say your max TP load is 80 and your timing value for column 80 was 16* @ 6800rpm and above. Now, let's say you were pushing a 120 TP value. Would the ECU keep the timing value of 16* or would it continue to retard timing even though you don't have anything else configured for a higher TP load? Like would the ECU bring the timing down to 14*? or would it stay at 16* the entire time?

-G

only accept the last timing value at the last TP load

Same with fuel as well. The ECU will always reference the closest cell value, when the load goes over the closest one is the last column. Thats the nice thing about TunerCode, it lets you play with those values.

Strictly speaking, this is not true. The ECU interpolates between cells.

You are correct. I didnt want to over complicate things.

What Dave said, but you don't want to really test it. Never allow the ECU to overrun your map. Always have 1-2 row buffer that are a good bit above your boost level to protect you incase you overboost. This way you wont loose an engine if something goes wrong with wastegate system.

Very good info! I didn't know if maybe the ECU continued to interpret your pattern kind of like it does between columns after you go outside the timing map's max values.

OK so mine was going to 140, that means that it was holding the same values past the stock numbers? I'm trying to understand this stuff lol.

Was 140 past your max TP value in your fuel/timing maps? If so, then yes.

So the ECU will 'interpret' between columns. So if you have something like

TP 80 100

7000 20 10

If you're at like 90 TP then your timing would be 15 or somewhere around there. But if you have a TP of 140 and go outside that range then the lowest your timing will get is 10. The ECU does no more interpreting after the final right-most TP column.

-G

I assume the charts were previously stock. I honestly don't know much about it, Haulin200sx is helping me out. He makes a bin for me, I give feedback, and he adjusts from there. I have my own thread for it.