I take you mean using the 02 feedback alot like you would the Trims.......if it's too positive add latency and vice versa......your trying to get your 02 feedback as close to zero as you can too right?

 

Yes in a perfect world 02 feedback should jump around as close to 0 as possible. It will never stay at 0 though.

What I meant by what I said was, lets say your low fuel trim is -8 at idle. This is a learned value, at some point the 02 feedback had taken a bunch of fuel out to reach 0, it did it's part and now the low fuel trim learned it and is staying around -8 so that the 02 feedback is closer to 0.

Now, you want the low fuel trim to be close to 0. So what you want to do is subtract some latency at 14v. You do this and then you will see that that 02 feedback is now adding fuel (because you just took out latency). This will eventually be learned by the low fuel trim. So lets say you got lucky and took out just enough latency to make the 02 feedback add +8 fuel. Then the low fuel trim will learn this and be at 0. Now the 02 feedback is happy at idle and should be around 0 as well. All is good in the world.

02 feedback is the big boss that works in real-time and the low/mid/high fuel trims are the little minons doing the big bosses bidding and learning from it.

make sense?

 

Yep.....tons of sense. You can watch in the log, O2 feedback starts positve and then as the low fuel trim goes up it....the O2 feedback goes closer to zero

So basically the O2 Feedback is all the little calculations that make up the changes in the fuel trims about every 4 minutes?

 

Yup, 02 feedback is making changes in real-time and the trims are the stored information.

 

Well....flashed in my new latencies.....car will idle perfect all day and the low fuel trims sit at about .8%-1.1% and my O2 Feedback moves back and forth between -.6% and 1.2%....so it seems my idle trims are finally dialed in! But I'm off to bed....I'll log my cruise trims tommorrow! Hopefully I can dial those in just as easily!

 

Alright...I'm slowing getting my mid trim in check. My low trim is positive while my mid is negative, so I'm going to add some latency.....but have a question...does it ever happen where your injector scaling is HIGHER than the actual size of the injectors? Reason I ask is my injector scaling is getting awful close to the size of the injectors, and when I add latency I'll have to bump my injector scaling up to compensate for the change in latency taking out some fuel at cruise.....do I just ignore that? I mean my fuel trims are getting much closer, so I should just continue as I'm doing, right?
Second quesiton I got is when I first start my car it sometimes runs extremely lean (17.5-18.1) I looked at the logs and it shows my O2 feedback not moving......but as soon as I "blurp" the throttle the O2 feedback starts working and it'll idle at the 14.7 range until I shut off the car again. Does anyone have any idea why this would be?

 

my PTE 780cc Scaling:
680


Latency:
4.6875 3.624
7.03125 1.992
9.375 1.344
11.7188 0.984
14.0625 0.744
16.4062 0.576
18.6768 0.456

trims, idle, and cruise are great.

 

Ok Im' just gonna say ... this topic SO needs to be added to the wiki ... hopefully someone who really knows the topic has the time >;-)

 

It's been awhile since I contributed to this thread so here are some big dogs:

RC1200's on both pumpgas and on E85

Gas Scaling-1044
latency-
4.7- 3.6
7.03- 2.184
9.38- 2.088
11.72- 1.296
14.06- .792
16.41- .720
18.68- .480

E85 Scaling- 680
the same as above except
11.72- 1.344
14.06- .864


I'll have 1600's up in a few weeks...hopefully sooner

 

not that i need these... but you are the man JB

 

I just moved to RC 1000cc to get ready for E85

Scaling: 835

Latencies:

3.6
2.184
1.56
0.936
0.672
0.432
0.336

This matched my scaled Denso 720cc AFR that I had before almost spot on (within .1)

Trims are perfect so far

 

I had always wondered how fast RC1000s are compared to stock and my FIC1050s. The RC's seem to be right in between. Slower than stock, but a bit faster than FIC1050s. SIze scaling is much less than my FIC1050s. You'll probably up around 90% IDC on E85 with no change to power (boost) levels.

 

On 100 octane, my IDC's went from 96% with the Denso 720cc's to around 65-66% with the RC 1000cc's.

I figure it will go back up around 90% with the E85. We will see soon.

 

FWIW, the RC1200s in the 57 trim we did that made 440whp were at 83% with a single non modded 255 on pump E85 (not our premix E85).

 

Aaron, what do you mean by premix E85?