OFT Basic tuning procedure
 

Update: 4/10/2014
Links to tuning info from Koadname47

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UPDATE 4/8/2014:
Just a quick update on the information that have been given by forum members and how I have been implementing them. This is not meant to serve as a means to an end guild. If you choose to follow these direction to tune your car, you do so at your own risk.,,^_^

*If there is enough request for pictures with instruction then maybe i'll do some step by step picture tutorials.

1:I used romraider to advance ignition timing: Romraider along with the required FRS XML definition can be downloaded from http://www.openflashtablet.com/produ...ads/index.html.
By adujusting base timing B under ignition timing-Advance around .5degree at a time and log for knock. Caution:you should leave base A alone as it is the fail safe map. I've been able to add on around 11hp over the stock OTS maps, of course these whp that I've logged only on Virtual Dyno so I can not guarantee the accuracy of the VD compared to a real Dyno, But my logs are done on the same HWY (very dead Hwy) and I'm only comparing my original stock ots tune of 169whp to the 180whp VD readout that I got from logging.
tip: so far I've been able to advance up to 2.5 degree with minimal MAF scaling.

2:As far as the adjusting the AFR, it appears that the fueling-Primary Open Loop that I was doing didn't do much. so I just reverted back to stock setting. haven't tried to adjust the closed loop fueling yet, but I will probably mess with it in the future if needed,<-this should yield better result since the closed loop runs off the o2 sensor.

3.adjusting MAF scaling will be updated when I can come up with a way to do it in layman's term.

So far that's all I have been able to gather, as more information becomes available to me I'll try to update it, also if you see anything that is inaccurate, please let me know so that I can revise this post.


-------4/5/2014-----------------------------------------
I have no previous tuning background so
Just to clarify, what exactly am I suppose to log with OFT?
So far Ive just been slowly leaning the arf and advancing the ignition timing while keeping an eye on my logs for knock but I'm not sure if I'm looking in the right places. Seems like adv multiplier is always at 1 no matter how lean i get...does that mean that it hasn't detected knock and haven't pulled timing yet? So it should be safe to keep advancing? 2nd.ly KC correction is always at 0 degree. While KC learned only jumps around when there's load. .which i believe it's normal.

Just wanted more insight on what you guys are doing and what are your procedures... and if what I'm doing is correct .
I'm not looking to be a professional tuner, just looking for basic tuning diy procedures. Thanks in advance

And yes I'm aware that theres an official thread here http://www.ft86club.com/forums/showthread.php?t=46468

leave the arf alone

You shouldn't be playing with AFR and ignition timing unless you're on a dyno as well. You could easily be losing power instead of gaining power, and making the tune less safe.

Ideally you'll tune for maximum power, then richen it up a hair and back off the timing a slight bit to make it safer on the street.

Simple, if you don't know what you're doing then I'd advise leaving it well alone.

Getting the MAF scaling correct so that you're consistently hitting the target AFRs is my starting point. Then you know the LTFT isn't trying to fight you.

Where are you changing the AFR and timing?

:word:

I've been altering the ignition timing advance in base timing A and base timing B and bringing up the Primary open loop fueling table.
currently at WOT my afr is at 12.1~12.8 from 4k to redline.. adv multiplier is steady at 1 and kc correction seems to be steady at 0 degree. LTFT and STFT are hovering around +/- 5%

I understand how dangerous it is and I thank you all for advising me to leave what i dont know alone... But with that said.. you'll never learn anything if you don't explore, and as long as I am doing it in a slow and coherent pace I don't see the danger.. That's why I've posted this thread asking for more help so that I dont blow anything up..

edit: here's a log of my current wot run http://www.datazap.me/u/hsayaovong/9...6-7-9-10-11-12

I understand what you mean, but I only have access to a straight road.. so I've been adjusting and logging my adjustment and comparing the result on virtual dyno for any gains or losses.. each new adjustment get's 4 or more wot pulls in 4th gear to make sure that if there is any changes it is consistent.

If your STFT and LTFT are off by ~5% or more you'll probably want to rescale the MAF to get that closer to perfect. If you want to look at that, you'll need to log AFR, AFR commanded, MAF voltage, IAT and fuel system status.

If the MAF scale is off, whatever AFR your tune is commanding won't be what is actually coming out until the trims stabilize, which for WOT will take a while.

Depending on the fuel, it's possible to keep advancing timing until you destroy your bottom end. Unless you have a dyno, I wouldn't play with that. Like others said, you can adjust your MAF scaling but you shouldn't play with timing unless you're on a dyno.

Even with "infinite octane" fuel wouldn't you get knock once you advance the timing so much so that this fuel is ignited to early before top dead center? Which would produce knock snd if you log for knocks and keep away from advancing to far how would you destroy your bottom end? (I'm not challenging your advice, I'm trying to understand my own understanding on the subject).

To my understanding without a proper aftermarket wideband o2 sensor most of my afr teaching is probably inaccurate anyways, that's the main reason why I should be monitoring for knock, correct?

@HSayaovong what I meant was where in those tables? Flat advancing/leaning out the whole table is not ideal.

Have you any idea what AFR you're eventually aiming for? The problem is that if your LTFT start taking fuel out you will run leaner than desired and that's not good.nif you want to do this, look on Romraider for basics on the ECU. There's some really helpful info here too as well as NASIOC. Don't just look for OFT based info, any Subaru tuning references will do. Just just walk into this blind, do your homework.

Yes the knock sensor should keep you relatively safe but if you're only monitoring KC then you're not seeing what's happening at WOT. Any idea how your knock learn data looks like over multiple pulls? You only have 1 pull in that posted example.

Mate Had a kook at you log , unless you have hacked away at the "Knock Control Advance Max A" table you have -1.5 to -2.0 knock correction happening between 6400-6700 that's the chunk out of your kc learned

http://www.datazap.me/u/hsayaovong/9...1274&mark=1040

you say you have been adjusting Base Timing A and Base Timing B. As far as i know Base timing A is for limp home mode or AVCS fail and not generally used.

You might want to read this post , i'm not guaranteeing its 100% correct but I think I should give you some more useful info

http://www.ft86club.com/forums/showthread.php?t=61820

It might be worth considering an E-tune from the OFT boys (since you already have OFT) its $200 and they will explain the changes they make. You will still learn and it will be safe, lots cheaper than than a damaged engine.

I am actually considering this option myself.

kc learned is your advance table. you probably shouldn't be messing with your base timing tables because one is you safe mode. I believe its A. ive only adjusted the timing advance which applies ones the ecu says its safe to (operating temperature and no knock present)

My target afr that I would like to have at wot is around 12.8~13.

I've been adding timing to both A and B when there's more then .8 g/rev load, <---which from what everyone is saying I should leave B alone because it's the failsafe map.

another weird thing that I've noticed is that if i increased my AFR beyound a certain point in the Primary open loop fueling table above .8 g/rev , the ecu seems to automatically add positive fuel trim which increased my afr to 11.xx:1 at wot, compared to a less aggressive map which produce around 12.8:1 AFR..
*although my afr command is set higher, it's actually running richer.. weird.... and i what area can i correct for this change

so if i see the kc learned drop like it did from 6400-6700, what exactly does it represent? should i be retarding in this area?

so only adjust base table A, got it.


here's the current full log of the map that is running in the car atm http://www.datazap.me/u/hsayaovong/full?log=0&data=1-7

Right, I wouldn't like to see any leaner than 12.7 at full throttle, you're unnecessarily adding heat to no real gain in power, which in return will make you more knock prone. Where did you get a figure of 13:1 from?

Also, why are you changing tables as low as 0.8? You're never under 1 on full throttle.

The reason the car is changing fueling so much is due to the LTFT caused by the MAF being off. 0.8 is right in the CL to OL changeover area so if you change the fueling there the trims will have a big impact.

Seeing the kc learn table drop is a sign of knock, 2 degrees pulled is a fair bit.

Stop just stabbing in the dark in the hope to achieve a target you've not set. Put an original OTS map back on the car and spend a few weeks reading and learning. Then start again. There is so much info about that just not bothering to learn seems idiotic.

If you are playing with OFT, I think the best suggestion (you may have already) is to compare your base map to the various stages of OFT tunes.

By looking at how they modify the base for each stage, you can see some of the logic behind the changes.
In RR the compare ROM feature tells you which tables are different and you can look at "difference" maps that reflect only the changes from one map to another.

Take your time, make small changes that you can log the results of, and know what you're looking at when you do. Don't listen to people who tell you not to try. You'll never learn anything (beyond general tips and tricks) reading on a forum. Get out there and do it, just be smart about it and take it slow.

The first thing you need is accurate calibration. Scale the maf properly in closed and open loop so that you're hitting targets with ltft turned off. Don't rely on trims to hit fuel targets, as they won't do so consistently.

You can absolutely tune timing on this car without a dyno (so long as your not on ethanol). You'll hit the knock wall on even the best 93 octane looooong before you reach mbt. You sound like you have a decent idea of what you're doing and have the right approach. Just keep doing it, and remember the process. Slow and steady wins the race.

If you need any help or want a second set of eyes, feel free to shoot me an email.

noo map A on romraider is safe mode. you should leave it be

Thanks, I might take you on that offer and hit you up someday for tuning advice,
Also thanks to everyone with their great idea and suggestions. All the response was exactly What i was looking for.
Any additional tips,tricks and technical know how is greatly appreciated.
Keep them coming.

If you take advance too far with race fuel or something that can handle without knocking what normal gas cannot, you can end up increasing the cylinder pressure high enough to bend a rod or do something else bad. You can also very easily start losing power.

Since the OFT tunes already have a lot of work put into timing, you're probably not going to get much by playing with timing. If anything, you'll probably muck it up and lose power. You might even break something. More advance is not necessarily better. Now if you made significant mods to the car, that would be a different story.

Oh, and you never said what fuel you're using. With 91 or 93, you probably will run into knock before driving up the cylinder pressure too high, at least at high rpm. At low RPM, I don't know.

I'm on 93oct. But what I've noticed is that there must be some kinda of primary limiter or something of that nature that keeps you from starying to far from the ots tune.
You can't lean it to much or adjustments will be made in ltft and stft for the difference in what the ideal afr it thinks it needs. That must have something to do with the maf scaling that you guys were talking about..*any links to more info on how to adjust the MAF scaling on romraider?* step by step tutorial would be awesome.

Also, I'm not looking to go all out and change everything about the safe ots maps that shiv provides. I'm only looking to ride on the knives edge of the tunes since the ots are made with a great deal of provisions to ensure compatibility with most vvehicles, i want too kinda undo what shiv's margin of safety.

*would be great if @shiv chimed in with the exact steps he took to input the margins of safety :) so that people like me can slow creep up the tune for more powwa.

I also would like if any of you guys that have oft and have done your own tunes to share it..i think shiv would be fine with tune sharing, that's the point of open source tuning right?

As others have touched on, blindly adding timing may not do anything for power (we've already touched on the safety aspect).

The keyword is "timing" and there is a perfect amount of timing known as MBT, maximum brake torque. That is the optimal timing where if you increase timing any further you no longer make any more power.

On this car I think you actually knock before you hit MBT but I wouldn't risk it personally.

The only way to advance timing is to do it on a dyno. At that point the only time to increase timing is when A) you are not knocking and B) extracting more power. It's VERY hard to do this on a street where you are not in a controlled environment such as on a dyno. Can it be done on a street, sure, but not recommended.

I would strongly advise you not to blindly add timing. There is also a threshold where you add too much timing and simply lose power. Other times you can add timing and knock.
Most tuners would recommend, including myself, that when you achieve MBT on a dyno you typically want to reduce ignition by 1-2 degrees for safety. (depends on the platform).

This safety comes into place for exterior changes, heat soak, octane differences, increased humidity, extreme temps, up hill loads and the like. You always want to leave a margin for safety, especially on a street vehicle.

It's a excellent you want to learn but keep in mind these engines are not bullet proof. :w00t:

you will never reach MBT on an 86 before you hit knock on pump gas. it just doesn't happen.

That's good to hear, since I'm on 93oct and i log for knocks i should be fairly safe to play with my timing"in small increments of course". Without to much fear of blowing something up right? And also by leaning base timing B alone for fail safe.

Also @jamesm , you don't happen to know of any tutorials on how to adjust MAF scaling do you? From the sound of everyone's response it seem that the wild swings in my stft and ltft are due to the maf scaling right?

you will run into knock before you reach mbt. you still have to be monitoring for knock, though :). just add small increments and log twice as much as you think you need to.

if you have any significant fuel trims being applied you would correct that with maf scaling before doing any WOT tuning. ideally you should be able to get them down to within 1-2% and turn off LTFT in open loop so that you can have a more consistent open loop AFR. i'm not sure if the table to turn off open loop trims (or should i say, the one that works) is exposed in romraider/tunerpro though.

Really interested in this thread. The OFT is going to make it possible for people to grenade their engine, and I want to make sure I'm not one of them!

It'll happen. Not to smart people who follow best practices, though. Unless of course they have some really shitty luck or fat fingers ;).

I am interested in the flash tuning process too. I have done a little tuning on my MR2 with a Apexi PFC and have taken the advanced EFI 101 class as well as read some books on tuning. But much of them deal with tuning live being able to see what cell you are on, making changes and watching the differences. With the flash system that we are using this procedure won't work. I am assuming that to tune with a flash system you would make a logged run on a dyno, look at the logged data, flash and repeat. Anyone want to share their procedure that works for them?

Closed loop MAF scaling:
http://forums.nasioc.com/forums/show....php?t=1427448


Open Loop MAF Scaling:
http://www.ft86club.com/forums/showp...&postcount=995


As far as adding timing, I would advise only adding timing over 2500 and 1 load. Then you're not likely to add tip in knock. The rest of the table has no influence over WOT so IMO there's no need. Unless of course you think partial throttle is lacking....

Everyone that is currently a "pro tuner" at one time or another was at the same stage the op is currently in. If the guy wants to explore,great. Just do in a safe manner. And what better way to explore? enlist the help and knowledge of a forum!

This is the second time you've mentioned leaving "B" alone, but at least twice posters have said that the one to leave alone is "A". Can someone clarify?

sorry, I meant leave A alone and adjust B., you can check for this in Romraider when you compare the different tunes, it's B that's adjusted for different tunes, not A.
Thanks for pointing that out.. didn't mean to confuse anyone.:bonk:

Yes correct for "flash" tuning sequence is, log, Analise results , change,flash ROM, log, Analise change flash ect.

To do true live tuning you would need a different ECU or emulator where some or all of the map tables are stored in RAM so they can be changed on the fly . I believe hydra http://www.hydraems.com/ can do this to some extent but it costs $$$$$ not really worth it for average person. Probably Motec and other as well.

Saw somewhere here where some Ecutek guys has a pseudo live tuning setup where they hijacked a couple on inputs to the ecu to switch/offset some custom maps on the fly for a sort of live tuning effect.

With ecutek you have 4 map modes, so you only have to flash once every 4 runs if you use them right. Combined with a ~1 minute flash time, it makes it far less of a pita.

hey @jamesm and @Kodename47 , i've updated the first post to reflect what you guys been saying and alot of stuff from the links that were provided. can you guys check it out and advise on revisions?
I would be great if we can get a thread with accumulated information to help people that are new to tuning and want to learn.

thankx

I asked about that a while ago, and the answer seemed to be "ain't nobody got time fo' dat." Basic tutorials and even written information is sorely lacking. Half of these threads would go away given even basic written documentation and stone simple "your first tune edit" guide.

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.

Is the stock o2 sensor good enough to use to OL MAF Scaling or is an aftermarket wide-band O2 a necessity ?

I keep on seeing/reading varying reports. My opinion on the matter is that you can use it for N/A tuning so long as the sensor has been scaled correctly. I have no idea what Shiv's O2 sensor scaling is like in comparison to the given ECUtek scale. It seems that the sensor is more accurate the closer to stoich (14.7) but loses it's consistency further away from that based on pressure and temperatures. Therefore I wouldn't do repeated runs without allowing a cool down period if you're doing OL fueling, this doesn't necessarily mean stopping just don't do WOT constant runs back to back.

To make OL scaling easier, you could set the map to a flat AFR of loads 1 and above - eg all cells 12.5/12.6 etc. This makes it easy to analyse and won't be an issue for a couple of runs that are needed for scaling. Due to the sensor accuracy, you want it as lean as possible BUT remember if your MAF scaling is already off then you could run leaner than the commanded AFR.

How I've been looking at it just for MAF scaling on an NA car:
- 1st runs with a map of 12.0/12.1 - If you've already got logs, you have an idea whether your scale makes you run lean/rich. Do a few pulls to get good data - I like 3 or 4 pulls from 2.5/3k to reline.
- 2nd runs around 12.5
- 3rd runs - fine tune with as lean as you're happy to go, but reduce timing a little to prevent knock. With the DI capability I personally would go as high as 12.75 but only for a couple of pulls.

That should be enough. If in doubt, always make the MAF scale a touch higher. I'd rather run 0.05 richer than leaner.

If you can visualise the data in graphs etc, you can see if the stock sensor starts to read inconsistently and then discard that data.

Once you can do this, I would seriously look into latency and PI/DI scaling as it's just an evolution of this technique.

Also worth noting on CL MAF scaling, as per @jamesm's screencast, don't go mental and randomly adjust each point. You want to adjust everything together.

After logging for an hour or so whacked data into CL Maf scale spread sheet see below. Look like CL area is pretty good only a couple of minir tweeks required.

Looking at the WOT runs I did for OL scaling similar to stuuf I sent you a while back it was off a fair bit Measured AFR 11.3-11.5, commanded AFR 12.3-12.5 (STFT=0, LTFT =+2%). Weird all the error in top end?

Unless I am doing something wrong ?