Romraider MAF tool

[bmx045]

Here is a link to the dyno study i mentioned: http://www.iwsti.com/forums/power-bragging/207168-2011-subaru-sti-baseline-pulls-initial-mods-custom-dyno-tuning.html

[B-BGTLimited]

You want them to be as close to 0 as possible, but they will fluctuate with weather changes to some degree and you shouldn't really worry too much about A, B or C ranges unless they get really high and stay there. The D range in the one everyone is usually worried about, as whatever number is in this range gets applied to the rest of the MAF in open loop. That means that if you're running 11:1 a/f at wot and you have -10% in the D range, your 11:1 could be more like 12:1 which is too lean and can cause knock and engine damage.

 

In the case of your tune, the tuner has set the D range so high, that it will never set and should never be anything but 0. You most likely will not hit 75g/s in open loop. I hit 60 or 70g/s while driving steady at 75mph going up hill. Anything more goes into open loop. Without steady drive time at a given g/s, the range won't move from 0. Since you won't be hold 75g/s it should always be 0.

 

Makes sense, I'm gonna have to mess with this a little to see if it helps out my tune.

[bmx045]

and here's my latest LV:

[NSFW]

I'm only passing on info I got from the romraider forum, you don't have to do it.

 

Some expanded info on the topic.

http://www.romraider.com/forum/viewtopic.php?f=33&t=4899

 

That RomRaider link contains pretty much everything I have to say on this subject.

 

Except for one thing - it is very easy to over-estimate the usefulness of Learning View. The AF Learning values move around a bit even without making any changes to the tune or the hardware, so if you use them to adjust your tune, you will probably just end up chasing your tail. The Knock Learning values are not terribly reliable either - the ECU picks up false knock often enough that if you pull timing every time you see knock in LV you will end up pulling way more timing than you should.

 

LV is good for an occasional sanity check, but logging is better, and lots of logging is best.

[B-BGTLimited]

That RomRaider link contains pretty much everything I have to say on this subject.

 

Except for one thing - it is very easy to over-estimate the usefulness of Learning View. The AF Learning values move around a bit even without making any changes to the tune or the hardware, so if you use them to adjust your tune, you will probably just end up chasing your tail. The Knock Learning values are not terribly reliable either - the ECU picks up false knock often enough that if you pull timing every time you see knock in LV you will end up pulling way more timing than you should.

 

LV is good for an occasional sanity check, but logging is better, and lots of logging is best.

 

I agree with this 100%... The car has the ability to learn, you want to keep this learning in a small window for a typical weather condition in your area, but if the air pressure changes then the learning will be off a bit and there should be no need to adjust it, the weather will change again and it will re-adjust... As far as the last learning block, if putting that value high does infact ensure you will always end with a 0 adjustment value in open loop then that is not a bad idea to do. I noticed mine had some - adjustment and I changed to the higher scale and haven't seen that come back yet.