OFT Basic tuning procedure

[Kodename47]

Originally Posted by HSayaovong

Wait, I can't seem grasp this... by apply change evenly across a section of the maf scaling table..wouldn't this create skewed and inaccurate result?
I.e reducing from 1.16v to 1.7v down .03 would have more of an impact on the lower voltage then on the lager one wouldn't it?
So by tackling each given voltage column and adjust each one to the ltft readout should yield greater accuracy shouldn't it?

Please advise. Thanks

An example, if you reduce every data point to 97% of it's original, the curve will remain the same shape but it will be smaller. The whole point of what I was trying to say is that the end result should ideally be a curve. Going and adjusting each point individually isn't the right way to do it.


Here's an example of what I mean, this is my S/C car on an earlier MAF revision. This is % change from stock scale:



You can see that it slowly increases. If that line was all over the place, which it would be if you did every point individually, then the MAF curve will be all jagged and not smooth which isn't ideal. There will always be some error, there are other ways to get around those once you start looking into it. Remember that MAF scaling is a starting point, not the way to cure everything.

[HSayaovong]

From the looks of it, maf scaling would be so much easier to dial in if we could see the affects from the changes in real-time and not just from loggs.. 15mins of adjustment in real-time would probably be equal to months worth of logging.

Anywho. Another question. If I'm only doing minor timing advancements and from the afr And fuel trim readout the affects looks minimal at the worst case scenario.
Is it safe for me to assume that it's okay to not chase after 0%ltft, besides, when i have something like a steady+ or -3%ltft and a +/- 3%stft the ecu have already compensated for the long term Rich or Lean automatically and as long my stft isn't going nutts it should be considered stable.

[mid_life_crisis]

Originally Posted by Kodename47

The thing is that there is a lot of information already on the web. The Romraider lot have been doing Subaru ECUs for years now and most of the way our ECU works is on their site. There's a few minor changes, namely the fact we use PI and DI and that info is already posted here. I could create a thread, but it would just be links to RR or NASIOC.

This statement is why beginners like me need posts from experienced tuners.
Even if the post is nothing more than "to learn about such and such, read this excellent post from NASIOC but be aware that this and this are different on the twins." and what those differences mean.
That last bit is critical in some cases and not all of us have the collected knowledge to know these things.

[Tromatic]

Originally Posted by Kodename47

The thing is that there is a lot of information already on the web. The Romraider lot have been doing Subaru ECUs for years now and most of the way our ECU works is on their site. There's a few minor changes, namely the fact we use PI and DI and that info is already posted here. I could create a thread, but it would just be links to RR or NASIOC.

Very few people will give away their ideal fuel and ignition maps it seems at the moment and would you risk running someone else's maps anyway?

The way I see it, Google is your friend and have a deep look around what's around already with Subaru ECU information. If you have any questions then ask.... That's exactly how I learnt. Read info, compare maps which will inevitably lead to more questions which you then research. I found it quite satisfying.

I'm talking about a very basic, simple, start to finish how-to. All of the documentation that exists assumes you already know what you are doing. The OFT tablet itself is stone-simple, it's everything else.

[shif7i7down]

I believe the lack of step by step tutorials on tuning efi engines like the fa20 is due to the fact that for people that knows how to tune, tuning is their livelihood and all information and knowledge that the tuners have are all proprietary information that they will not give out freely.

If you really want to learn, go buy a cheap Honda civic for 2grand and practice tuning the crap out of it.
It hurts less to destroy a 2g car the it does to destroy a25g car.

Just my .002

[Tromatic]

Originally Posted by shif7i7down

I believe the lack of step by step tutorials on tuning efi engines like the fa20 is due to the fact that for people that knows how to tune, tuning is their livelihood and all information and knowledge that the tuners have are all proprietary information that they will not give out freely.

If you really want to learn, go buy a cheap Honda civic for 2grand and practice tuning the crap out of it.
It hurts less to destroy a 2g car the it does to destroy a25g car.

Just my .002

Man, I'm not asking for proprietary info or secrets. I'm asking about a basic guide for beginners on how to use the various tools available. Yes, there is info on the web, but none of it aimed at stone-beginners starting from scratch.

Maybe I have to write the fucking thing.

[HSayaovong]

Originally Posted by Tromatic

Man, I'm not asking for proprietary info or secrets. I'm asking about a basic guide for beginners on how to use the various tools available. Yes, there is info on the web, but none of it aimed at stone-beginners starting from scratch.

Maybe I have to write the fucking thing.

My thoughts exactly, that's why I'm doing this "Basic tuning procedure" thread, you are welcome to join in with your findings. I hope to be able to learn enough to not destroy my engine at the same time to also provide layman's instruction to others that may want to follow in my footsteps.

[Kodename47]

3/4 months ago I was in the same boat as you lot but I took time to go and look into as much info as I could.

The problem with a basic tuning procedure is that everyone likes to have a different approach. What I like to do may not be the best way, but it works for me.

Go here:
http://www.romraider.com/forum/viewt...hp?f=33&t=5299
Direct Link - https://sites.google.com/site/asubie...gguide/ver-1-0

Then look through this:
http://www.romraider.com/forum/viewforum.php?f=33

Then read some of this:
http://www.ft86club.com/forums/showthread.php?t=30418
http://www.ft86club.com/forums/showthread.php?t=57279
http://www.ft86club.com/forums/showthread.php?t=53064

Have a trawl through that. The How To section on Romraider is pretty good as there are a lot of newbie questions on there.

[HSayaovong]

Thanks for the the links. Will definitely follow in your for steps and go through them.

[phrosty]

The CL scaling howto mentions logging A/F Correction #1 (AFC) and A/F Learning #1 (AFL). Are these STFT and LTFT respectively?

So the basic idea, after filtering out any bad records, is that adding STFT and LTFT will give a percentage to adjust the grams/sec under the record's corresponding voltage bin?

[Td-d]

Originally Posted by phrosty

The CL scaling howto mentions logging A/F Correction #1 (AFC) and A/F Learning #1 (AFL). Are these STFT and LTFT respectively?

So the basic idea, after filtering out any bad records, is that adding STFT and LTFT will give a percentage to adjust the grams/sec under the record's corresponding voltage bin?

Yes, and yes.

[Kodename47]

Originally Posted by phrosty

The CL scaling howto mentions logging A/F Correction #1 (AFC) and A/F Learning #1 (AFL). Are these STFT and LTFT respectively?

So the basic idea, after filtering out any bad records, is that adding STFT and LTFT will give a percentage to adjust the grams/sec under the record's corresponding voltage bin?

It really is that simple, you just need to know how to read the data and what to do with it. In CL don't go and change each value individually, look for trends. Try and adjust as much as possible as a flat value. General thoughts seem to be that you would rather it be slightly negative than positive.


If you don't know what to do, feel free to post graphs etc.

[phrosty]

Excellent. I've made an app to automate it for me -- even better than the linked howto because it properly interpolates between bins. If anyone is interested I can make it a little more user-friendly and throw it up on a webpage.

[shif7i7down]

Sounds like something that can be created in excel, and all you had to do was paste in your logg files.

Which would be awesome if someone with the excel technical know how could make one. And share it on here