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thats what im getting caught up on, its a calculation, not someting 'real world' if it makes sense. there are so many variables for working it out (just the ones you've mentioned, i'm sure theres heaps more) if one of those is slightly out, your motor wont be making the power it could be, or it goes bang. now what if 2 or 3 or more of those numbers are slightly out? will 1-2 degrees of timing really allow for that?

for any given motor, how much info will you have to give the computer/how much calculating do you have to do so the computer can work out how much timing to give? how technical is the info you'd have to know? will you need to know all the in's and out's of the fuel you choose to run? sounds like it may be pretty involved/time consuming, time that a tuner could be fidling with ignition maps, getting the tune right, without any doubt, coz he will hear it start to knock/see the power drop off, and will find the safe limit of the motor.

other thing is, from what i can gather, the computer is chasing peak cylender pressure, and trying to get the main flame front burning at that point? but, wouldnt that casue massive detonation in a turbocharged motor? (possibly NA too?)

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I'm gonna reply in your original post.

thats what im getting caught up on, its a calculation, not someting 'real world' if it makes sense. - Yes; the idea is to make the calculations close to real world. Remember, the laws of physics are universal and irrefutable. So it can be predicted. That is what real tuners do now - based on expierience.

there are so many variables for working it out (just the ones you've mentioned, i'm sure theres heaps more) if one of those is slightly out, your motor wont be making the power it could be, or it goes bang. now what if 2 or 3 or more of those numbers are slightly out? will 1-2 degrees of timing really allow for that? - Time will tell; but based on our research to date - we will always be underpowered by a degree or two...cost of safety. But again; for a street driven car; do you really want to wring out that last 10 HP and cost a motor with one bad tank of gas, drop in fuel pressure, clogged injector, hot day, etc...

for any given motor, how much info will you have to give the computer/how much calculating do you have to do so the computer can work out how much timing to give? how technical is the info you'd have to know? will you need to know all the in's and out's of the fuel you choose to run? - There is a lot of set-up and it is a pain in the ass; not much I can do about that. The only additional info you need to know for timing is bore, stroke, compression ratio and Octane of Fuel. Well that is the goal really; if we have to get more specific than octane then we are going to have to go by Octane and Zip / Postal Code and keep a database online with the latest fuel make-ups - kind of a pain; but do-able.

sounds like it may be pretty involved/time consuming, time that a tuner could be fidling with ignition maps, getting the tune right, without any doubt, coz he will hear it start to knock/see the power drop off, and will find the safe limit of the motor. - Tuning with a knock sensor is a better add on; but not all EMS's have them. If you do have one then we can include that into our calculations. Initially, you may be right - but remember as boost, AFR change - your timing needs to change too as fuel will burn at different speeds. So you have to work timing and fueling together; it is nice to have something that can do that for you. A computer can never replace a human obviously, but it can do a lot of the heavy lifting for you... think about having a full tune at 90% of what you want before you even show up at the dyno; it will save a lot of money and time to just tweak that last 10%

other thing is, from what i can gather, the computer is chasing peak cylender pressure, and trying to get the main flame front burning at that point? but, wouldnt that casue massive detonation in a turbocharged motor? (possibly NA too?) - Don't confuse results with input - the result of max cylinder pressure at 12 degrees ATDC for a piston motor is always the best mechanical advantage. The reason why timing changes is to accound for the fuel burninig speed / engine speed / load / AFR etc in order to get the RESULT back to that 12 Degree mark. So FI, NA, whatever - the end goal is the same. The software just helps you backwards plan for the end goal you want; and double checks to make sure pre-ignition is not likely to occur.

Awesome questions so far guys. It is nice to see a highly educated skeptical community out there; anything less and we can't improve the software.

I know this sounds fundamental, but how did you come up with 12 deg ATDC, when surely this is markedly affected by rod/stroke ratio.

Geometery - I should have said Typically 12 deg ATDC; anything less than 12 - and the force of the explosion is pushing directly on the crankshaft; as opposed to rotating it; anything after 12; and the force is diminished by the volume changes in the cylinder; IE you have wasted some of the torque possible by firing too late.

While extreme cases can affect things; in reality the direct relation ship between 1 piston, rod and crank is the same regardless of bore and stroke etc. You have O-O basically; so the two circles are always going to relate to each other in the same degree path regardless of circle size or the length of that straight line (the rod).

As always I cannot dictate what degree to use in the map - just like the AFR map; the end user has to decide that for themself.

Here is a link http://www.innovatemotorsports.com/resources/chevy502.php about it. About halfway down the page.

Some real detailed information can be found in "How to Tune and Modify EFI Engines" by Jeff Hartmen; but you gotta buy the book.

Chapter 1 of Corky Bells Maximum Boost , "An Engineering look at the basics" , explains this pretty well .

The side note on page 5 mentions 20 degrees ATDC which I think is intended to be a guide and next to it is a two dimensional graph of cylinder pressure vs crank angle .

I can see where it's desirable to have a self tuning system but I don't see how you can get around knowing detonation thresholds without making it happen . On the bleeding edge it wouldn't take much to damage something and people are understandably reluctant to take the risk .

Something that might be worth looking into is an inline device capable of signalling the octane value of the fuel in the rail because usually that and the AFR have a lot of say in how much advance an engine can take before it detonates .

I don't know if such a thing exists but if it's possible to have an ethanol content sensor maybe something for ULP is possible .

It's getting OT I know but ethanol would be a more controlled substance than ULP so easier to work with in high ratios .

Cheers A .

Edited by discopotato03

If you are going to go down that road; I would recommend the Fiber Optic Spark Plugs; that contain a pressure transducer. Then you will really know when you making maximum cylinder pressure. But they are kind of pricey.

Again, keep in mind this is for a street tune; this is not a bleeding edge tune by any stretch. This is for the people who are too cheap/lazy to go and play on a dyno for hours just prior to track day. With 340 at the wheels in my RX8 I almost never get to go WOT anyways; so I don't really need that extra few ponies.... this is software for people that think like me.... LOLZ

Edited by PPO2 Kane

i'm still not getting how it targets peak cylender pressure.

ideally the 'event' takes place at 12atdc? now, not confusing input with result, look at a tuned ignition map (cbf finding one lol) and look on an average tuned map, at around peak torque ~3500rpm, you will have a given figure for ignition timing, look closer to 7500rpm, and you will probly have similar timing figures, meaning that 'event' should be taking place alot later yes? how can you have similar advance when the piston is moving at twice the speed, and still retain the same end result (ie event at 12atdc)? does the change in volumetric effeciency changes the flame speed/delay till the 'event' THAT much?

i'm still not getting how it targets peak cylender pressure.

ideally the 'event' takes place at 12atdc? now, not confusing input with result, look at a tuned ignition map (cbf finding one lol) and look on an average tuned map, at around peak torque ~3500rpm, you will have a given figure for ignition timing, look closer to 7500rpm, and you will probly have similar timing figures, meaning that 'event' should be taking place alot later yes? how can you have similar advance when the piston is moving at twice the speed, and still retain the same end result (ie event at 12atdc)? does the change in volumetric effeciency changes the flame speed/delay till the 'event' THAT much?

- The answer is no - chances are the later RPM portions of that map is over-retarded for "safety".

Well your parameters (air fuel, engine temp, air velocity, piston velocity, fuel make-up, spark plug location) do affect timing to a great degree - but the real reason why we see timing maps like this is because of the "rules" of tuning timing.

Think of the tuning process when done on a dyno or on the street over a 1-3 hour tuning session.

Generally accepted rule: You have to retard timing at the torque peak of the motor; and slowly advance timing through the higher RPM's. Looking to keep the EGT as low as possible while still making power; timing map would kind of make a _/\_ in a 3d view of one load scale. Ok cool; but no one really knows by what degree to do this; so they guess / go on expierience - if the motor makes good power and doesn't grenade then life is good.

Then we have our dyno tune - one session; so what is going to happen? The motor is going to get heak soaked; so that will obviously affect power output, egt and propensity to detonate. Now our tuner straps the car down and starts his run (let's assume he is on an eddy current dyno); he gets his WOT pull and holds the car at his target RPM and Boost/Load cell he is going to play with... then using the AFR, Dyno readings and EGT, he starts to advance the timing.... he see's that he is making power. So far so good; now does he advance until it starts to ping and then back off a few degrees? If he does that; then he has a motor that has already knocked some; and will be MUCH more likely to knock again until it fully cools down. So you can tune one cell at a time; and then let the motor fully cool - but that is not really cost effective. So he decides to use the EGT and dyno to sneak up on the power - without overdoing it; cool - so he has what feels like a good powerband - no knock and the motor seems safe. For that day and that tank of gas. Again; coupled with his expierience he cross compares what your motor is doing to what other motors have done.

Notice all of the subjective terms..."back off some" - how much? It doesn't say back off 3 degrees.

With this in mind; the timing maps commonly in use make sense; they are safe - make good power; and if you don't know any better then life is good. I have seen FD's running 45-50 degrees of advance at 7500 RPM; and I have also seen the same motor set-up running 30 degrees of advance; with both motors on the same twin turbo set-up; and both owners loved the car tune.... so which one was better?

I think the biggest timing related issue is that most people consider it a "black art"; and as long as their motor is happy; and they are making the power they wanted - then they just call it good.

Now if you have an in-cylinder scope / fiber optic transducer; you could play with the timing and KNOW that your reaching max cylinder pressure at whatever degree... but they are expensive. The last option; is to use the physics model - and simulate an in cylinder pressure sensor... according to the research I have (and references on my site); this simulation is really close to actual. And we'll know more once we start to test with the University folks.

Edited by PPO2 Kane

FINALLY!!! I have finished the Help Files. Everything is Documented except for the Appendixes.

Happy Reading... You all have NO IDEA how much I hated doing this... LOL

http://ppo2performance.com/docs/?page_id=15

  • 2 months later...

PPO2's Tuning Software Introduction Video

IMPORTANT ANNOUNCEMENT: Version 1.5 will be released in May with MAF based tuning supported!

This copy will work until May 15th 2009. *** Updated Version 1.4***

Sorry for the delay folks; I had some issues to resolve.

I will try to get out new versions of the Beta as I fix MAJOR issues.

Link to Download Version 1.4 -

ZIP Clicky!!!

UNZIPPED Clicky!!!

You MUST have MS Access 2000 or later to use the Beta version. If not you will have to wait until I move it to a standalone.

How to Use the Wizard Help This sets up the motor for Baseline

How to Import a Datalog into Baseline

How to Create a Tune and View

User Guide is in progress under "Help".

Sample Log File to play with - http://www.mediafire.com/?mmntwl0wknm

For Hondata - use the % to Add or Remove; since your maps are not in Duration or Duty Cycle.

For PFC - UPDATE!!! Apexi PFC Now Has the Duration Map available!

For IntX - Be sure to set up the auxilary fueling in the Injector Setup Window by Checking the Auxiliary Fueling Block. And use the % to Add or Remove also.

For AP Racetuner - go ahead an set the Manifold PSI Scale up in load - and see what kind of logs you get; I don't know how it will work yet - but if you are bored. I do know the HP calculations will be wayyyyyy off.

Go to http://ppo2performance.com/ for more information...

thanks for the update

will look right into it

going to get a wideband 02 sensor kit, a eprom ecu 84-pin socket read/write kit and some chips and go over my tune

cheers for all the hard work :blink:

  • 10 months later...
mazda.gif

PPO2's Tuning Software Introduction Video

IMPORTANT ANNOUNCEMENT: Version 1.6.3 is now available with MAF based tuning and import defaults!!! 1.6.3 also works with Vista !!!!!

This copy will work until March 30th, 2010. *** Updated Version 1.6.3***

Fixes:

- Save Existing Template Error

- MAP Based tuners having to put in a MAF scale / you no longer have to.

- Import RPM bug in Vista

- MAF Voltage errors when tuning with a MAP EMS

- Bulk Target AFR Loader! No more typing!

I will try to get out new versions of the Beta as I fix MAJOR issues.

Link to Download Version 1.6.3 -

VISTA USERS

**** You must also put the file into a trusted location so the code can run. Read more about it here: http://office.microsoft.com/en-us/access/HA100319991033.aspx - VISTA ONLY

Zipped File Clicky!!!

You MUST have MS Access 2003 or later to use the Beta version. If not you will have to wait until I move it to a standalone.

How to Use the Wizard Help This sets up the motor for Baseline

How to Import a Data-log into Baseline

How to Create a Tune and View

User Guide is in progress under "Help".

Sample Log File to play with - http://www.mediafire.com/?mmntwl0wknm

For Hondata - use the % to Add or Remove; since your maps are not in Duration or Duty Cycle.

For PFC - UPDATE!!! Apexi PFC Now Has the Duration Map available!

For IntX - Be sure to set up the auxilary fueling in the Injector Setup Window by Checking the Auxiliary Fueling Block. And use the % to Add or Remove also.

For AP Racetuner - go ahead an set the Manifold PSI Scale up in load - and see what kind of logs you get; I don't know how it will work yet - but if you are bored. I do know the HP calculations will be wayyyyyy off.

You must set up the load in the scale your EMS logs in - so if your EMS load is in percent but is logged as full numbers - set the load scale up accordingly (10 instead of .10 etc). This is important.

Go to http://ppo2performance.com/ for more information...

**** To save your import file defaults, select the columns in the import window and press "Save Defaults". The next file you import will default to the columns from your set-up.

**** If you are Tuning with a MAF Sensor; you need to go into Options and set up your MAF scale from your factory EMS - so you can get your MAF Scale grouped by your voltages.

We're back bitches!!!!! With some new cool stuff.

If you get your Target AFR's into THIS format in excel.

BulkLoaderExcel.gif

Then you can copy and paste them into Baseline (AFTER YOU SET UP YOUR ENGINE). Just Go to Options, and then the Target AFR Bulk Loader Button. Then Highlight all the old stuff, right click and delete, then right click and paste new stuff. Be sure the Load and RPM Scales are accurate.

BulkLoaderBaseline.gif

if it was me i wouldnt trust auto tune code written by 3rd party groups or people

particulary for platforms that dont support it, ie the powerfc and other ecu's

the auto tune in the motec and autronic etc would be bulletproof

as its had lots of testing, r&d, development, time and $$$ spent on it to get it perfect

if datalogit had autotune im not sure i would trust it, and it sounds like this thing youve mentioned is similar

a 3rd party app to suit a number of ecu's

- The answer is no - chances are the later RPM portions of that map is over-retarded for "safety".

Well your parameters (air fuel, engine temp, air velocity, piston velocity, fuel make-up, spark plug location) do affect timing to a great degree - but the real reason why we see timing maps like this is because of the "rules" of tuning timing.

Think of the tuning process when done on a dyno or on the street over a 1-3 hour tuning session.

Generally accepted rule: You have to retard timing at the torque peak of the motor; and slowly advance timing through the higher RPM's. Looking to keep the EGT as low as possible while still making power; timing map would kind of make a _/\_ in a 3d view of one load scale. Ok cool; but no one really knows by what degree to do this; so they guess / go on expierience - if the motor makes good power and doesn't grenade then life is good.

Then we have our dyno tune - one session; so what is going to happen? The motor is going to get heak soaked; so that will obviously affect power output, egt and propensity to detonate. Now our tuner straps the car down and starts his run (let's assume he is on an eddy current dyno); he gets his WOT pull and holds the car at his target RPM and Boost/Load cell he is going to play with... then using the AFR, Dyno readings and EGT, he starts to advance the timing.... he see's that he is making power. So far so good; now does he advance until it starts to ping and then back off a few degrees? If he does that; then he has a motor that has already knocked some; and will be MUCH more likely to knock again until it fully cools down. So you can tune one cell at a time; and then let the motor fully cool - but that is not really cost effective. So he decides to use the EGT and dyno to sneak up on the power - without overdoing it; cool - so he has what feels like a good powerband - no knock and the motor seems safe. For that day and that tank of gas. Again; coupled with his expierience he cross compares what your motor is doing to what other motors have done.

Notice all of the subjective terms..."back off some" - how much? It doesn't say back off 3 degrees.

With this in mind; the timing maps commonly in use make sense; they are safe - make good power; and if you don't know any better then life is good. I have seen FD's running 45-50 degrees of advance at 7500 RPM; and I have also seen the same motor set-up running 30 degrees of advance; with both motors on the same twin turbo set-up; and both owners loved the car tune.... so which one was better?

I think the biggest timing related issue is that most people consider it a "black art"; and as long as their motor is happy; and they are making the power they wanted - then they just call it good.

Now if you have an in-cylinder scope / fiber optic transducer; you could play with the timing and KNOW that your reaching max cylinder pressure at whatever degree... but they are expensive. The last option; is to use the physics model - and simulate an in cylinder pressure sensor... according to the research I have (and references on my site); this simulation is really close to actual. And we'll know more once we start to test with the University folks.

:banana:

if it was me i wouldnt trust auto tune code written by 3rd party groups or people

particulary for platforms that dont support it, ie the powerfc and other ecu's

the auto tune in the motec and autronic etc would be bulletproof

as its had lots of testing, r&d, development, time and $$ spent on it to get it perfect

if datalogit had autotune im not sure i would trust it, and it sounds like this thing youve mentioned is similar

a 3rd party app to suit a number of ecu's

I can totally respect that. Would it help if you saw the math?

:)

I am not sure what this means...

Kane, long time no speak brother. I havent been keeping up with the news since i got the new ECU, im STILL sorting out a few issues and i've just bought a motorbike so progress on the car has slowed down (read: stopped).

ill send you an email with some updates soon.

I am not sure what this means...

thing of all the good things a Nuclear sign can mean in the context of a piece of a equipment that is basically a controlled explosion.... :P

i would 'hazard' (thank you, thank you, enjoy the veal) a guess and say it's a bad thing the emoticon is referring too...

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