Ok, now I'm getting this straight in my head. It took a few days when you don't take notes.

I've got the latency at 1.32 @ 14V, scaling 1462 . Both trims are around around -10, so they are finally about equal. Going to bump the scaling back to 1624 and I should be legit...

 

Almost there.

With the Scaling at 1624 and 14V Latency at 1.320V I was at a perfect 0 for cruise, but -6 for idle. So I'm going to drop the latency one notch. I think this should do it. Should know by tonight.

 

Well this is crappy. Dropping the latency made the trims flop and the idle went to +2 and the cruise jumps around between -12 and -4. So it's like I'm in between the resolution I need.

AND an even bigger problem is that with the injectors scaled like this I can't get my fuel map to give me the proper logged AFR's. I have the fuel map bottomed out at 7.4 and I'm running mid 12 AFR's.

Anyone got some ideas?

 

Is your MAF scaled correctly?

 

I've never touched the MAF scaling. What's involved?

 

https://www.evolutionm.net/forums/ec...-maf-pics.html

 

OK, I looked at those, but it seems like the chicken and the egg.

My car has always ran and tuned great with the intake I have. Only thing that has changed is these massive injectors.

So in theory could I go and scale my injectors around 1350 to get my AFR map working again and then use MAF scaling to get the fuel trims correct? That's going to be some serious work.

 

Too high scaling then. Also do you have lean spool on or off?

FYI I tuned another Evo on the 1450's this weekend and that Evo only scaled to 1390 and the fuel map matched what is normal.

 

Lean spool is off, via setting address 1680 and 1684 both to 1500.

So I'm going to drop the scaling down: available options are 1271, 1329, and 1392. 1271 would put them in the typical 12% less than stated value. But I know that 1390 can get the fuel maps to work.

So what about the fuel trims?

I know that to balance the trims I need about 1.320 s of latency at 14V. I plan on keeping that the same, is that correct? I can then go in and scale the MAF to bump the trims into the proper range... Or should I use the listed latency of 1.178 s at 14V and adjust the MAF scaling differently at those specific loads to balance the trims.

Also, have people rescaled the MAF to higher setting than 1600Hz on big turbo cars, or is that not needed.

 

yes they have. I would assume you would want to scale it higher and follow the curve.

 

This is my plan...

Based on earlier settings I'm going to adjust scaling to 1329 and use 1.178 (spec'd) latency at 14V. This gave me cruise trims that were within acceptable values. It also created high trims at idle.

I'll then use MAF scaling to correct the idle trims.

I don't plan on rescaling the MAF larger, as I don't know what the benefit would be.

 

Tried a little MAF scaling, didn't seem to help too much, but I'm going for a second round of adjustments...

Injector scaling at 1329 put the AFR map right where it should be though. Hopefully I can get the MAF scaling to correct the trims.

 

OK so MAF scaling is helping at idle I've almost got it perfect. But the transition from idle to cruise in terms of Hz values is pretty fast/close.

Idle is between 30-50 Hz, and cruise is between 100-200 Hz.

I tried a flat profile (195) between idle and cruise, but that makes the cruise trims a little too low, as it ends up adding fuel in the 100-200 Hz range compared to stock scaling (which ramps 175-200). So I'm going to try having the idle scaling up at 200 and then there will be a major jump back to normal settings at the 100 Hz level which is around 175. Hopefully that will stop the transition from getting too much fuel and dropping my cruise trims.

 

Hey, those latency values look familiar/similar, Bryan.

I got those scaling/latency values by driving on a flat road at a constant speed for long periods of time and multiple sessions. With 1624 on 91, it was pretty much within spec (3 low, -2 mid). I didn't have to mess with the MAF scaling. With the scaling, the fuel map looked weird. Bryan had to drop a bunch of cells to 7's and 8's.

On E85, the trims were closer (0, 3). When you get there, the scaling that worked was 1008.

Good luck with the injectors.

 

I've got some settings that are working OK for now. I'm tired of logging trims as I've been doing it for over a week and it drives you crazy hoping the trims will be ok and then having them creep out of range slowly after 30+ mins.

Scaling:1329
Latency: From the data sheet included with the injectors
2.784
2.112
1.680
1.368
1.176
0.984
0.816

MAF Scaling:

19: 195
25: 195
50: 195
The rest: stock settings