caught a post by johnbradley about doing this to while working on increasing economy

i had wanted to add some timing to my 70-80mpg cruise area to see what happens/if the car likes it, yet i dont want to have to blend a big spike into the main map.

my car is not heavily modified and the whole egr system is still on the car. FAA bit 11 (egr disable) is set to 0.

-how does the egr table determine when and how much timing to add based on the table? i think i read something about knock based?

-is this the cleanest way to add cruise timing?

any info would be greatly appreciated.

 

I'm searching for the same thing...
I'm sure I could get better cruise mpg.

 

It works like a Subaru. It will add timing till it gets knock, reset, and try again. I can get it to support around 44* normally.

Aaron

 

i wound up just putting it in the main map rather than trial and error. im running 37 at cruise with a bad front o2 and getting 25mpg highway. easy passing in 5th without getting in boost. only minor annoyance is it take so little pedal pressure to maintain a cruise speed its hard to keep it steady.

 

well actually use this formula
actual timing advance = high octan ignition map + high octan EGR enabled.
Keep in mind that LOWEST fuel consumption is on 42-43 degree (that is summ of these 2 tables).
Should also keep in mind that by default EGR enabled advance is only between 1500-2500rpm and 30-70 load, however it can be modified.

 

Wait, so If I wanted to use this, I would have to re-enable the EGR system right? Asking because I have all of my EGR stuff removed and it blocked off on the intake manifold.

So what I am getting at is, I'm probably going to get a check engine light if I re-enable it? Best way to fix that? Plug the solenoid back in and just stick it somewhere?

 

from my point of view - since you are already OFF EGR system - just increase timings in your high octan ignition map in range 30-70 load and 1500-2500rpm up to 42.
Do not forgot to make it smooth.

check knock sum and adjust if needed.

 

Turn it on in whatever periphery you turn that off in, then go to Periphery 2 and set it to 0x0001. EGR CEL, Misfire, FPR solenoid, all those will go away and it still works.

Aaron

 

Would like to recall this message - John's decision is much better.
Now I have STOCK timings in cruise and tuned high octane EGR enable table ( in order to have no more than 44 in cruise).

Now I have HIGH timing only in CRUISE but not on track

 

I just noticed something. If we are doing this, should we zero out the EGR MAP offset tables since no exhaust gas is entering the intake manifold and changing the pressure?

 

why can't it be done to just putting 44's right in high octane ignition map ?

in addition, one question here: I have EGR system enable/disable set to 1 in 'Other Ecu options' section and in peripehry bits FAA bit.11 (enable EGR duty) set to 0

in this case is ecu adding timing from egr map to my high octane map ? (I have egr hardware removed)

 

You can add 44 to the main map but poor quality fuel can cause knock and if your knock setting are tweaked it wont correct for it.

I run 41* in the high octane map and leave 6-8* depending on RPM and load in the EGR map. Per the periphery change, I dont know how it works when you do it that way necessarily but the previously outlined method I use works just fine.

 

that makes sense. ive been trying to add it to my main high oct map. ..

will be following

 

Is this for E85 as well?

 

Does the map offset or any other egr settings need monkeying with ? Egr duty etc.

Or just set periphery 2 @ 0x0001 adjust egr timing map and go with it?