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Discussion Starter #1 (Edited)
Increasing ignition advance via intake then tune

So i have a thought/theory as well as many questions..
I have purchased an AEM f/ic. I did the research on the piggyback, however my error was not realizing you could not advance ignition.. I have been doing some research on how to counter this, and i have come to a few options.. The one that i don't think is possible is increasing the base timing of the vehicle.. I am not familiar with a way at least. The next which i am intrigued by is one that i have learned through Mr Cap him self. I've been following through his research since becoming a member on this forum..

So here's my thought. The AEM F/IC allows you to retard timing, but not advance it, so in order to control /modify the timing i would have to have a way to advance it, then retard it to get it where i want it. So after reading through this thread i have come to a realization..

Cap as well as others have stated that by removing the veins, moving the MAF up, etc the ecu is tricked into believing the air flow isn't there, thus increasing timing. The way cap has countered this is by either modifying his fuel pump to pump more fuel, or increase the injector size. This will push more fuel into the engine as well as increase ignition advance, thus increasing power output.

All of this may have been covered before, but in theory, if i use, say a 3" intake, and fool the ecu; In theory, it should advance the timing.. Using the F/IC to clean up the fuel trim using the stock injectors/fuel pump i should be able to gain the power same as the injector/pressure mod.

Would anyone like to shed some light on this subject? Go into further detail, i am all ears.
This could also be useful to those running other piggybacks who would like to modify ignition times as well.
 

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I wish I knew what you were talking about. I'd feel so much smarter!
 

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I think you are working way to hard and trying to re-invent the wheel.
If you really want to have the engine do what you want get a PFC and learn tuning from books and those that have good knowledge. The PFC will give you the right kind of control and will advance your timing without trying to fool anything and it can factor in other variables to keep your timing in check, in real world conditions where other parameters can change engine dynamics. Once you mess around with timing there is no going back if you mess up so get the right equipment.
 

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Working with Piggys ia a little Awkward.. You advance the Timing, only to retard it again..

USUALLY there is a way to Intercept the MAF Sig, and either 'Re-Map' it's output or Do some sort of Calculation of Input of MAF to Output VS Rpm Vs TPS VS Boost.. or some Combo of choices..

PFC Standalone is the Ultimate.. but you are Starting from Square ONE.. Piggys, you are Slightly Altering existing Maps.. and you have Knock Retard..

You can Do the 3" Maf Housing.. but then the Car will not run without the Piggy.. If you just Re-Map the MAF Sig, you can leave the Stock Air Box Alone, and the Car will run with 'Zero Maps' in the Piggy..


Cap
 

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Discussion Starter #5
These were all thoughts. The ignition timing i'm not all that worried about as it is still a NA 1zz and the left over power to be gained is minimal at best.. I am more just exercising the ideas trying to gain the knowledge. as with CAP, i just like to know how things work and interact with each other. This is the simplest way to learn the tuning. Like cap said, a zeroed out map will be stock, and any modifications on top of that alter the numbers coming from the ecu(or going to). A PFC is just a little more in depth as it is a full stand alone. I really thought about it, and even found a few GREAT deals of sub $600, but i opted out so i can stay with the obdII. And, in the future i plan on turboing so the ability to advance timing isn't as needed.
 

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These were all thoughts. The ignition timing i'm not all that worried about as it is still a NA 1zz and the left over power to be gained is minimal at best.. I am more just exercising the ideas trying to gain the knowledge. as with CAP, i just like to know how things work and interact with each other. This is the simplest way to learn the tuning. Like cap said, a zeroed out map will be stock, and any modifications on top of that alter the numbers coming from the ecu(or going to). A PFC is just a little more in depth as it is a full stand alone. I really thought about it, and even found a few GREAT deals of sub $600, but i opted out so i can stay with the obdII. And, in the future i plan on turboing so the ability to advance timing isn't as needed.
Don't get me wrong, I am all about DIY and trying different things however in my opinion the best and fastest way to learn is though a PFC. I also learned a great deal from books and those that understood Copilot. Like you I have to be ODB2 compliment so when it comes to emission testing It takes me no more then 15 minutes to swap out the PFC for the stock ECU. After a great deal of understanding I then understood the limitations of the stock ECU and the best part is I did not have to experiment to find out what I already know. In regard to advancing timing for better performance it is not as simple as that as you may not only run on the edge of destroying your motor but also not achieve max horsepower.

If you still want to do it the hard way I recommend the Camcon unit because it would be a safe way to tune.
http://www.newcelica.org/forums/showthread.php?t=213242
 

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Discussion Starter #7
i would love to go pfc, but again, when i go turbo i would like to stay obdII and i won't be able to just swap the ecu back from the pfc with a turbo. I may look into the camcon. i'm gonna play with the f/ic for a little bit first. I'm not going to mess with advancing the timing until i get something dedicated to doing it.
 

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Another way to go is the 'SMT' series of Piggys..

I've seen Forum Posts on the installs of SMT4's and 6's on Toyota PU's.. of the 90's.. but nothing newer than that..

The SMT series is up to 8 now, and has lots of Stuff.. The Ability to Advance and Retard the Timing Sigs going to the ECU from the Engine Triggers, is a WAY cool Feature..

Lots of Different Calks you can do on Various Inputs VS Outputs..

The Damn thing is Almost a Standalone.. and they do make one that is..

But you'd be out on your Own Figuring Wiring and Programming of the Thing..


This is the Unit that DP Tune was going to put into a Spyder ECU for Andres02 Early on in the ECU Mod Talks.. After a lot of Phone Calls and E-Mails to him, ( DP Tune ).. he just did not have the time to donate to a Small Population Car like the Spyder.

Cap
 

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Discussion Starter #9
All other engine management aside, i think for my purposes this will be perfect. :) i still may go out and get an f/ic when this car comes solely track based, but for now it is my dd, soon to be weekend fun car.
The more i look into this device, the more potential i see it has.
The ability to "clamp" the MAF and o2 sensor signals so that you can limit the voltage the car sees, thus preventing the car from relearn due to changes with your maps.

Another thought on this increasing ignition advance, the FIC gives you the ability to clamp the MAF signal that the ecu receives. Similar to the larger intake diameter or the moving the MAF out to alter the voltage going to the ecu, If i were to clamp the MAF signal to a specific voltage all the way up the rpms at step increments, and then modify the fuel trims to counter, in theory, this should work. When i get my harness and uego in i may test this theory.

A neat little modification that isn't specific to this is a shift light powered by the VTEC engagement. At what ever RPM you choose, by simply connecting an LED of sorts up to the positive out of the VTEC. This turns the Shift light on at whatever rpm you set it at.

All in all, this is what i need for the time being, and probably the future as well. I am happy with the power of the car for what i use it for, and when i decide to turbo i won't need the ability to advance timing, a pressure sensor for boost monitoring, the ability to modify the o2 and MAF signals being fed to the ECU which allows for basic open and closed loop tuning.. This should be sufficient enough for me.
 

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The Idea behind Clamping the MAF Voltage going to the ECU, is to trigget the ECU to go to Open Loop, so the Piggy can then Play with it's internal Fueling Maps, and not fight the Learning Process of the ECU..

It goes like this.. Use the Calibration feature of the MAF input VS Output to get the Ignition Advance where you want it in Closed Loop ECU running.. and the Fueling is done with O2 Sensor Feedback by the ECU

When you get to the Engine Load Point where you want to start messing with Fueling, you Take the MAF Voltage to something like 5.0 Volt Output.. that will force the ECU to go to Open Loop, and not read the O2 Sensors.. and Not Corect it's Internal Fueling Maps by the O2 Sensors.. So the Fueling AND Ignition is now done by the Piggy..

And then on the Back Side of this, when the Engine Load Drops to some Lower Calculated Spot, you will then Unclamp the MAF Voltage going to the ECU, and Stop Making Fueling Changes to the Injectors, and the ECU falls back into Closed Loop, and the World is Happy Again..

You can not Mess With Fueling using the Piggy to Control Injectors UNTILL you force the ECU into Open Loop.. Else the 'Transition Points' between the Closed Loop and Open Loop can get a little 'Ruff'.. and will not be repeatable..

Cap
 

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Discussion Starter #11
i'm not to worried about modifying closed loop, just exercising some ideas. wouldn't it be possible to alter even the closed loop by having a clamped MAF signal and altering the o2 signals going to the ecu?

In theory, i should be able to tune both open and closed loop maps.
Clamp the MAF voltage the modify the voltages of the o2 signal to alter the closed loop fuel maps.

Then alter the fuel trims for open loop???

I still have many blanks and so many questions.

I'm learning so much and some stuff is blending together so bare with me.
 

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Discussion Starter #12
what are the specifics for when the car goes into open loop? What variables is the car looking for?
TPS, MAF voltage, etc?

If i am able to put the ecu into open loop but still keep the MAF voltage down..... Is the ecu still reading from the MAF under open loop? or is it only going off of fuel trims?

To finish my previous statement, which i am unsure is valid; If i am able to put the ecu into open loop but still keep the MAF voltage down wouldn't it keep the ignition advance?
 

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what are the specifics for when the car goes into open loop? What variables is the car looking for?
TPS, MAF voltage, etc?
That is the $50,000 Question..

Do some Searches looking for Posts by WTS , he di a LOT of Piggy work for his Turbo Install..

If you start logging and Charting, and watch the 'Dither' of the AFR's you will see the Point where the Fuel Mixture stops Wandering above/Below 14.7, and will snap to 13. That is when the ECU jumpes into Open Loop..

I have talked to a person who is running a Stock Spyder ECU, in a Spyder, and a 1.6L Variant of the 1ZZ. He Proclames the ECU NEVER goes into Open Loop, as the Calculated Load, on the NA 1.6 Engine will not trigger the Loop Change. ( So his AFR's ALWAYS stay at 14.7 during the Race.)..

That tells me the TPS is not used in the Calculation to go to Open Loop. It's Likely just an Air Flow* RPM to get the Fill Volume of the Cylinders ( GM Calles it V.E. for Volumetric Efficency.. if the VE gets above a certain Value, then Richer Mixtures are required, and Open Loop is the Only way to do that)..


If i am able to put the ecu into open loop but still keep the MAF voltage down..... Is the ecu still reading from the MAF under open loop? or is it only going off of fuel trims?
The MAF voltage is used to figure out how much air is entering the engine.. and then How Much Fuel will be required.. You can't force Open Loop, without Fooling the ECU with the MAF Voltage .. so if you clamp/Alter the MAF Voltage of the ECU, then YOU are required to do SOMETHING in the Piggy to add the Proper Amount of fuel, as the ECU is now Brain Dead with Bad Info.. but at least is's not recording stuff, and altering it's fuel maps..

To finish my previous statement, which i am unsure is valid; If i am able to put the ecu into open loop but still keep the MAF voltage down wouldn't it keep the ignition advance?

The only realistic way to get the ECU into Open Loop, it to toss some big MAF Voltage at it, and it will then TRY to toss LARGE amounts of fuel at the Engine.. and then the Ignition Advance will Retard ( Somewhat ), and the Ignition will follow the Curve for the RPM.. so the Ignition advance will change as the RPM changes, but the 'NEW' real Ignition Advance curve will have to be made by you.. using the Actual Air Flow.. Actual RPM, and if used, boost gauge.. AND...don't forget your IAT Calks.. if you do not corect ignition advance by Intake Air Temp, you'll blow stuff on warm days..

And now that you clamped the MAF Voltage, the Fuel that the ECU is going to try to toss at the Engine will be wrong.. so it's up to you, to do the Calks for the fuel in the Piggy..
Cap
 

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Discussion Starter #14
AS FAR AS I KNOW...
The ECU is in Open-Loop during these 5 conditions only:

1. Cold Start for 180 seconds or until O2 sensors heat up.
2. Warm Start until it has enough sensor data for o2 feedback
3. Hard Acceleration – based on load and environmental conditions
4. WOT
5. Fuel cut. At 1400rpm during decell and at the rev-limiter

There is no one point where the ECU enters open loop under hard acceleration. It can be as soon as 33%TPS or not until 5000rpm or some other place depending on conditions and load.

If your scanner doesn’t actually display open loop status then it can be found by watching the O2 sensor voltages.

Start in 1st gear at 2000rpm with the coolant up to at least 176F.
The O2 voltages should be bouncing.
Slowly raise the RPM until the O2 signal/s goes dead rich and stops bouncing.
Note the RPM/TPS where the O2 stop dithering.
Start in 4th gear at 2000rpm and repeat.
Note the RPM/TPS where the O2 stop dithering. Was it the same as the 1st gear run?
i'll post more later. when i find. lol
 

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It has taken me the better part of three years putting up an argument with Kevin Beane only to find out he was right all along. The PFC for what it costs is worth every penny and there is so much support.
 

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Discussion Starter #17
It has taken me the better part of three years putting up an argument with Kevin Beane only to find out he was right all along. The PFC for what it costs is worth every penny and there is so much support.

Eventually i plan to, but it's going to have to wait till either my next emissions(6 months) or when the car is track only. eventually i do plan on going that rout. For now, i am just trying to fully grasp the the concepts involved with tuning, and how each thing interacts with each other. Since i already have the f/ic, it's a great way to start without causing any/to much damage. lol I'm trying to learn as much as i can before i take the big step to something that will have to be fully tuned in order to fully work.
Anyways, Wideband should be in either tomorrow or Monday. I will be looking/logging the a/f ratios. I'll post some of the logs up when i get them. lol

Maybe, depending on how the taxs pan out i'll get one sooner as apposed to later.
I'm just going through my list of what i need/want:
 

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In my opinion

An OEM engine will not benefit much, if at all, from additional ignition advance. Let me re-phrase to be technically correct; TECHNICALLY if you advance the ignition timing you will ALWAYS make more... that is, right up until the point where the advanced timing causes a pressure spike that may damage internal engine components.

Since temperature and octane are only a few of the variables regarding ignition advance that fluctuate, it is wise for the factory to leave some headroom for those condition in the timing tables for the OEM engine. Going uphill, on a hot day, and it should not ping when using the right octane- thanks to the foresight of the OEM programming.

Yes, you can remove that safety net and advance the timing to GAIN a little something. But that is exactly what you are doing: removing a safety net.
 
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