Newbies Guide to Logging

[HolyCrapItsFast]

done!

 

[Grinder34]

Also when you log like this you want smooth throttle inputs to minimize the effects of tip-in and over-run

Holy, you mentioned the above in another thread (emphasis added by me). A follow-up is: are there any logging situations when you do want sudden throttle position changes? Only when tuning tip-in and over-run tables?

 

[HolyCrapItsFast]

Exactly... You need to effect a fast throttle change when tuning tip in enrichment and you need to do it for different throttle deltas. Meaning a short jab of the gas would be a small delta and a hard jab to the floor would be a very large delta. You could be at 50% throttle and effect a change in delta of 3% and it will add a specified amount of fuel. Subsequently if you are at 75% throttle and effect the same change in delta you will be adding the same amount of fuel.

So tip-in relies mostly on throttle delta and not necessarily throttle position. Except more fuel will be added per delta at low throttle positions than they will at high throttle positions. :tup:

 

[inferno19d]

HOLY rusted metal batman a ton of great info that I will have to reread at least 5 times to get a good understanding of it...

 

[Alin]

HOLY rusted metal batman a ton of great info that I will have to reread at least 5 times to get a good understanding of it...

I am on read 3 and still need to reread more haha. :tup:

 

[HolyCrapItsFast]

If you have any questions feel free to ask! :tup:

 

[inferno19d]

How can you ask a question? I am still trying to figure out what it all means... LOL

 

[HolyCrapItsFast]

:lol:

 

[ICY STi]

How can you ask a question? I am still trying to figure out what it all means... LOL

Thats what i would have said too. great thread Holy!!!

 

[HolyCrapItsFast]

If anyone needs me to explain something please ask! If I can improve it to make it simpler to understand I am open to ideas :tup:

I only want to help you all to understand your cars and to know when or how to recognize problems... Granted some of the information in a log is open to interpretation but I can help you to narrow down the information into something tangible.

 

[sti_newbie]

how about some explanation on mapping strategy? e.g..what do you tune first? Fuel, ignition, then boost?

Also, how do you know where to stop advancing or retarding timing and how do you get to LBT without the use of a dyno? a knock log might be useful for timing but is it safe enough to knock and then retard a couple of degrees?

 

[HolyCrapItsFast]

how about some explanation on mapping strategy? e.g..what do you tune first? Fuel, ignition, then boost?

Also, how do you know where to stop advancing or retarding timing and how do you get to LBT without the use of a dyno? a knock log might be useful for timing but is it safe enough to knock and then retard a couple of degrees?

The short answer is Fuel first then a combination of fuel, timing and boost. Yes it is safe to observe a little knock and then back it down till you see no knock. This is common practice. As long as it is not knocking all the time, a couple of degrees is not going to do anything. Download Virtual Dyno. It will help you see your power gains/looses.

The long answer is I personally start by defining everything very conservatively at first, rich fuel, low timing, low boost (no waste gate duty). Then I start calibrating for closed loop fuel and timing. (the key word here is calibrate, not define. Defining fuel come later) For the most part, Stock timing is good in closed loop but you could adjust it further to improve smoothness and response. Essentially I will start with a smoothed stock fuel map and smoothed stock timing and low boost (no waste gate duty) and then calibrate the closed loop MAF region till the logged parameters for A/F correction and A/F learned together are with in 3-4%. This gets the AFR's out the tail pipe to match the fuel map. I will then define the fuel map and/or timing map in certain areas for fuel economy or to improve response. Knowing how to do this is key though and it takes experience to get it right.

After that I will calibrate my WOT MAF so the AFR's at the Wide Band match the fuel map while boost is low. Then bring boost up and keep calibrating the MAF while keeping an eye on knock. Keep doing this till you have reached target boost. Adjust timing as needed to counter any knock. Once the MAF is calibrated, you can now start defining your fuel map by leaning it out. When I define fuel for wot, I am observing knock at the same time. Knock can be seen by observing feedback knock and learned knock parameters in the log and also observing dynamic advance multiplier to be "1". You can define your WOT fuel by leaning the fuel map at WOT and form 4000 rpm to about 11.3 to 11.5 AFR. Usually this is from load cells 1.75 and up. In my experience, this is the ideal AFR for the STi. Then start to add timing till you start to observe feed back knock and then back off the timing 2 degrees. Keep doing that till you are happy with the results. If you are comfortable doing so, you can further lean out fuel at RPM's lower than 5500 but be careful and compare your results with a reliable dyno plot using Virtual Dyno.

Observing knock is actually a combination of observing power gains and knock parameters at the same time and the best way to do this is to use Virtual Dyno software to dyno-plot your logs. Even though your log may not show any knock, The dyno plot may suggest otherwise because it shows you have lost power which could indicate that you are actually seeing knock or that you have not achieved MBT.

Essentially Fuel, Timing and Boost have to be all adjusted together, but if you calibrate your fuel first and just maintain 11.3-11.5 AFR, you should be able to just go right into boost and timing together. My reason for maintaining such a rich AFR is to help control Exhaust gas temperatures and also allow me to use more aggressive boost and timing. It builds in an inherent level of safety because street tuning while using Virtual Dyno leaves a certain level of uncertainty. On a real reliable dyno, there is no doubt and the results are your guide.

It takes experience to know the comfortable starting point and to be able to pick out the subtle differences and I don't recommend anyone just start tuning their own cars unless they have a clear understanding of the previous information and the relationship between timing fuel and boost.

To make VirtualDyno as repeatable as possible, always use the same exact stretch of road to do your run and try to duplicate all of the conditions each time. Start the run at the same RPM and in the same gear every time. Check the air in your tires and feed the software the most accurate information you can when defining the profile. It should not be used to determine how much power you are making, but to see what the differences are between runs. Also try to do all of your tuning on the same day. Environment has a profound effect on the numbers

 

[Doppelganger]

First off thanks for creating this thread George and second off thanks for the necrothread [MENTION=5742]sti_newbie[/MENTION] since I didn't notice this thread was here.

It has allot of good info I'll have to read when I'm in insomnia mode tonight.

Sent from my ONEPLUS A3000 using Tapatalk

 

[HolyCrapItsFast]

I edited my previous post for clarity :tup:

 

[sti_newbie]

Thanks for this [MENTION=9]HolyCrapItsFast[/MENTION] . I will have to get back to this in the morning, too tired atm, but I appreciate that you take the time to give us some genuine replies. Will get back with more questions!
[MENTION=2822]Doppelganger[/MENTION] Insomnia mode reached haha

 

[sti_newbie]

[MENTION=9]HolyCrapItsFast[/MENTION]

I totally understand what you are talking about.

So, from what you have said, the x-axis on the maps is MAF and the unit I suppose is g/rev. Can you log this parameter so you know exactly what is the load column you are using?

 

[HolyCrapItsFast]

If you are looking to adjust the MAF scale then you will be looking at a 2D table with a top and bottom row (in ECUFlash it is a left and a right column). The top row is MAF voltage and the bottom row is G/s. You will correlate the voltages in the MAF scale with the reported MAF voltages in the log.

Essentially you would observe a MAF voltage in the log and observe the fuel trim error (A/F Correction #1 + A/F Learned #1) at that voltage. That will correlate directly to the voltages in the MAF scale and you would apply a correction to the MAF at that voltage based on the trim error. So if you observe a +5% error at a certain voltage in the log, you will apply a +5% correction to the G/s that correlates to the voltage in the MAF scale.

When you make an adjustment to the G/s you need to isolate all of the individual voltages in the log one at at time by filtering your log data for that particular voltage and then average out the results to apply the error correction. Again your total trim error is A/F correction #1 PLUS A/F Learned #1.

Check out my tuning guide. It will explain the process in detail. :tup: http://www.netzonexpress.com/Files/HolyCrapItsFast_TuningGuide.pdf

 

[sti_newbie]

Great info man. Thank you very much for sharing!!
Btw I have tagged you on my member journal thread but I guess you have the tagging system somehow switched off?
Please have a look when you can. In the meantime, i will read your tuning guide. Thanks again!