Lean under boost!! - Page 18

TouringBubble · Feb 4, 2009, 05:26 AM

Do you have your maps rescaled to control fuel/timing at 125 load?

That sounds like you're hitting a point in the MAF scaling table where it flattens with increasing airflow. That would cause a rise in AFR if the map values were flat. If your fuel map is in the 10's, then you should be able to ramp it down after 5000 to prevent that lean shift.

No, don't increase fuel pressure above the stock setting. That is a rising rate regulator so it should be fine. To much pressure is bad as you get poor fuel atomization.

4g94T · Feb 4, 2009, 01:46 PM

yup my timing / fuel maps are rescaled to 130%

i made my MAF scaling similar to yours and that did the trick

because mine used to be a flat 255 from 800hz and above, but now that i changed it to where the value increases, it helped keep my AFR steady

i understand now.
i still have some fine tuning to do though.

sykou · Feb 5, 2009, 10:25 AM

so you guys got good results without rescaling the table to hertz? I thought 255 was the max you could go with the tables rescaled by the way...kinda confused here...

4g94T · Feb 5, 2009, 11:10 AM

Rescaling it is just another way to view it in Hz instead.
It has no effect, it just helps for logging because it logs in Hz

Touringbubble, did you notice after upshifts during WOT it leans out?
Like from 2nd to 3rd

TouringBubble · Feb 10, 2009, 08:00 AM

Quote:

Originally Posted by sykou

so you guys got good results without rescaling the table to hertz? I thought 255 was the max you could go with the tables rescaled by the way...kinda confused here...

I'm using a different scaling. This was an odd ROM and had different scaling values. 255 is the max value (8-bit) if you take the scaling equation out of the picture.

Yes, I got the results I wanted with the tables I posted. Give it a shot.

4G, I haven't looked in to AFR on shifts as this was an auto car. I do have one 5 speed tune in the works but weather and travel has kept him from logging recently. I'll be sure to look in to it though.

If you are seeing odd occurences on shifts, you can adjust the fuel map in the load/RPM area where the shift takes place. You stay in open loop on a shift, so the changes to the MAF values will cause a shift there. You should be able to adjust the map to correct the issue pretty easily.

4g94T · Feb 18, 2009, 01:15 PM

Thanks TB for sharing your MAF scaling values

I wish someone could find the correct location for REV LIMIT in ECUflash, that would be awesome to be able to increase it

Complink · Feb 27, 2009, 08:42 PM

^+1 i agree

OZ Rally · Oct 7, 2009, 08:49 PM

So any update on this? I seem to have similar issues too. I go a bit rich into boost then the car stumbles. After I let off the gas or shift the car stumbles again. In boost my wideband reads 11.0 AFR, idk if that's the max it reads or if that's what it really is. Right now I'm playing with maf size, scalings, fuel tables and ignition tables.
Some help please.

TouringBubble · Oct 20, 2009, 08:25 AM

11:1 should not be the max that the O2 reads, but if you have an Innovate product, you may want to verify the scaling using LM Programmer.

If you log airflow Hz in EvoScan, you should be able to use that data to dial in the MAF scaling table. Basically, as airflow (boost) rises, you'll need to increase the MAF scaling table in that Hz range to compensate for the extra fuel needed.

Increasing the MAF size value will also help, but it will increase your load level across the board. The issue with this is that it can cause drivability issues since the cruise load increases and you technically crush the WOT resolution in the maps. Increase this value only if needed.