Situation: I've tuned with hondata & uberdata and understand that with these systems, fuel is measured as injector duration, with the fuel curve peaking at max torque. So higher the number more fuel, fuel peaks at max torque and falls off. I'm accepting this as fact, someone can shatter my reality as needed.

situation part 2: i have a friend (yes contrary to what people say) with an evo with the autronic PnP system. He's had it mildly tuned but recently changed some piping around. I took the opportunity to boot up the laptop and observe the autronic system for my first time. As he drove, i heard a sound which i identified as a slight pinging. So we laid off boost and continued with the day. He setup a tuning appt for tomorrow but went ahead and emailed me the cal file.

So i've got his calibration file and i'm looking at the mass amt of options compared to what i'm used to staring at. I'm asking this question as an attempt to gain knowledge, not an attempt to start tuning autronic or the likes, just to gain some knowledge.

back on topic, via base fuel, i notice that autronic's fuel table is based on volumetric efficiency with a range of 0-200. So that's an instant change, fuel isn't measured based on duration but rather the efficiency of the engine? So what i'm wondering is, if i am looking at a fuel curve in terms of efficiency, will fuel peak at maximum torque? Also, am i correct to say that fuel is based off volumetric effieciency of what the engine can consume? if so, couldn't a car running autronic have a fuel map calculated with pen & paper if the variables of efficiency were known?

basicly, i'm looking at said evo maps and i notice the fuel map seems rather flat, with only slight changes here and there. shoudl fuel still increase as load increases? should fuel increase also as rpm's raise? Would a peak in fuel come at peak torque or rather peak efficiency of the engine?

also, how the hell do you guys get used to reading load in terms of kpa? where is the vacuum transition into boost? Is there a way to view the fuel in a 2d map, or would that be pointless?

I know its alot of questions, I should probably dig up Ben Strader's book at my house and investigate within it more, but i couldn't remember if it went into this kind of detail. Any help is welcomed. basicly a standard fuel curve i would have would rise and peak with torque with hondata/uber. on autronic i'm seeing a roughly flat curve for load & RPMs.

 

If you would sell your Honduh and get a car that actually goes fast you'd have one of these on your own car instead of that Honduhata.

200kpa = 1bar
300kpa = 2bar

The Autronic will compensate for compressor/engine efficiency as rpm increases. Typically you will have to decrease the fuel value as rpm increases under x load.

Learn the keyboard. Using the mouse sucks. G pulls up a graphical view. Enter modifies the current site under graphical view. Insert adds a new column or row to the matrix. All these hot key's are listed under the help menu.

 

The ECU takes care of all the injector pluse width calculations. It assumes your injecotrs deliver fuel in a linear manner. You also need to be looking at the A/F target table.

If you want 13.5:1 A/Fs at 0 PSI boost, you set the target A/F table to 13.5:1 at a given RPM site and 0 ambient pressure site. If you are at sea level, this will corespond to ~100kPa. You can default the VE table to 100% across the board and your A/Fs should be reasonably close to the target A/F table until you reach the points of major torque change. Once you have the wideband on it, you can change the VE table so that the A/F matches the target A/F. The Autotune feature basically does just this, only at a fast rate, if I understand the Autronic manual correctly.

Downloading the Autronic manual would probably help a ton on understanding how the Autronic works. It's really quite briliant. Once you get the VE table tuned, if you want to change the A/F ratios, you adjust the A/F target table. If you change a hard part int he motor, but you want the A/Fs the same, you change the VE table.

 

Changing the target a/f table is only necessary if you are using an Autronic wideband, which is able to take advantage of the mixture table and autotune. If you are using another wideband, you must change the values by hand



Modified by nimr0d at 8:16 PM 4/19/2005

 

i know about the niffy little features that autronic has about instantly being able to change the A/F ratio, just never really stared directly at thier fuel tables to see how they worked.

so when i looked at them, i was like, this isn't a fuel table, its just mapping efficiency of the engine. But interesting nonetheless to play with the stuff first hand and see how it works.

but as colin said, with a wideband other than the autronic, you must manual tune, rather than autotune, atleast in my understanding.

 

does anyone have any screenshots of the autotronic system ? Ive never messed with it and was just curious as to how its setup

 

Yes the Autronic fuel table will look different than most systems out there. The reason for this is because the values in the fuel table are a percentage of the Base Fuel Cal Multiplier number... example if you base number is 5.5 and the fuel table site is 100 then the pulse width will be (excluding startup,warmup,charge temp enrichments) 5.5 milleseconds *if you are at 100 KPA (zero vacuum zero boost)
The base number is multiplied X the manifold pressure behind the scenes... so our example would have 11 milleseconds of pulsewidth at 200 KPA(14.5 psi boost)

So when you look at the Autronic fuel table the numbers may all be very similar, and at high load when the compressor efficiency falls off the fuel numbers will actually go lower if everything else(fuel pressure, a/f ratio) stays the same.

When looking at the numbers vs. RPM, yes they will model the engines VE so you will start reducing the fuel by 5000-8500 or so depending on the motor.

Feel free to e-mail me with any Autronic questions.
Kevin

 

Kevin.....

You are very observant! Not many people realize the way the software works!

In most systems the tuner is responsible for figuring out how much to change the desired InjPW as manifold pressure goes up...the Autronic unit simply follows the laws of physics.

Of course, the actual InjPW is a function on the base fuel multiplier AND......the Compression Ratio, The Stoiciometric A/F value you have in the software, the Charge Temp estimation %, and the Target A/F value set in the target table......thats all BEFORE any compensations or corrections take place for the acceleration or deceleration, cold start, warm-up, anti-lag...etc etc

-Ben

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by seen4ever &raquo;</TD></TR><TR><TD CLASS="quote">

but as colin said, with a wideband other than the autronic, you must manual tune, rather than autotune, atleast in my understanding.</TD></TR></TABLE>

With the new SM4 that is now available, you can use any linear A/F meter you like for the Autotune feature as well as any datalogging you want to do.

The earlier SMC/SM2 versions can only use the Autronic A/F meter

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EFIGUY &raquo;</TD></TR><TR><TD CLASS="quote">

With the new SM4 that is now available, you can use any linear A/F meter you like for the Autotune feature as well as any datalogging you want to do.

The earlier SMC/SM2 versions can only use the Autronic A/F meter</TD></TR></TABLE>

i didn't realize the new SM4 was out yet, wasn't it famed to incorporate autotune for ignitioni back in the day? I thought it was going to have a new knock sensor to attempt to autotune ignition as well, nonetheless thanks for the info guys.

 

the SM4 does have a knock sensor per the autronic website... I just with the Evo PnP boards were an SM4 board

the slight pinging was caused by the timeing offset in autronic being lower than it was suposted to be. it was actually running about 3 degrees more timeing than thought. the PLX wideband was reading within .1 of the autronic analyzer. and with the resistor network i built i should be able to tune with the PLX from here on out. that is after i fully grasp how to use the autronic system.

Jeremy

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by skunk2 teg &raquo;</TD></TR><TR><TD CLASS="quote">the SM4 does have a knock sensor per the autronic website... I just with the Evo PnP boards were an SM4 board

the PLX wideband was reading within .1 of the autronic analyzer. and with the resistor network i built i should be able to tune with the PLX from here on out. that is after i fully grasp how to use the autronic system.

Jeremy </TD></TR></TABLE>

No it does not yet have the Knock sensor module. This is an optional upgrade that can be added at a later time when you buy the ECU. It is supposed to be released within the next month or so. It will use any stock OEM knkock sensor on the car and can be tuned in much the same way any other manufacturer's settings would be.

I have spoken to several people who have tried the PLX wideband with a resistor network. It doesn't seem to get the job done all the time because of the required dierential output of the 0-1v scale the Autronic meter provides. For example if the battery voltage changes in the car even slightly the meter needs to compensate, and a resistor network would not do that.

Let us know how it goes though if you do have some sucess over the long term.

 

The Innovative LM1 can have an active electonics module added that will work with the SMC and SM2 autotune feature.

The target A/F table IS NOT specific to the autotune feature. Yes, you need to change the VE table manually to get the desired A/F ratio, but ideally, you would set the VE table so that your actual A/Fs match the target A/F table. Essential, that's what the Autotune feature does. It compares the actual A/F ratio tot he target A/F ratio and adjusts the VE table to make the two match.

 

That's correct. One of the most important steps to do before actually tuning the ECU is to setup the Target A/F table whether you are using autotune or not.