AEM FIC finally out
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From: Calgary
Originally Posted by jiggarex,May 30 2007, 03:08 PM
Also if it can't control AFR then how would u tune an turbocharged s2000? Wouldn't the tuner have different ratios for that setup.
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From: AEM Electronics R&D
Originally Posted by jiggarex,May 30 2007, 02:08 PM
Also if it can't control AFR then how would u tune an turbocharged s2000? Wouldn't the tuner have different ratios for that setup.
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From: Maryland
Originally Posted by DelSolid,May 30 2007, 01:28 PM
Excellent question.
De-tuning has been a problem for the last 10+ years but gets worse with each successive ECU release as the ECU's become more robust.
It happens when you try to fight the ECU rather than work with it (like attempting to change the AFR in areas where the OEM ECU is in feedback mode).
The design criteria used while developing the FIC was specifically chosen to prevent detuning. we do not try to brute force the factory ECU to do something it does not want to do. We dont intercept sensor signals and double them and other hokey stuff like that. In early testing we jacked a 350Z's MAF sensor to more than double the proper value and the afr only changed 0.3 points! it detuned us instantly.
Since the FIC controls fuel by intercepting the ECU's injector outputs, it allow the ECU to see and control the engines sensors normally, with very minimal monkeying around. As long as some common sense is used while setting it up then de-tuning wont be a problem.
De-tuning has been a problem for the last 10+ years but gets worse with each successive ECU release as the ECU's become more robust.
It happens when you try to fight the ECU rather than work with it (like attempting to change the AFR in areas where the OEM ECU is in feedback mode).
The design criteria used while developing the FIC was specifically chosen to prevent detuning. we do not try to brute force the factory ECU to do something it does not want to do. We dont intercept sensor signals and double them and other hokey stuff like that. In early testing we jacked a 350Z's MAF sensor to more than double the proper value and the afr only changed 0.3 points! it detuned us instantly.
Since the FIC controls fuel by intercepting the ECU's injector outputs, it allow the ECU to see and control the engines sensors normally, with very minimal monkeying around. As long as some common sense is used while setting it up then de-tuning wont be a problem.
Thanks! good info
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From: Decatur, GA
I think this will probably be the setup to have for anyone on a budget, SC guys, and some mildly boosted turbo guys. For anyone with a built motor, I would aim more toward the AEM EMS though.
It seems like the initial setup should be fairly straightforward, yet the tuning process will be similar to many other piggybacks.
What this will likely mean-
You on a dyno with the dyno logging AFR
You logging parameters from the FIC
You logging parameters from the stock computer
You tuning the boost controller as all of this is going on (if used)
You will then have to take the data from these three/four sources, analyze it, and determine what changes to make to the FIC. This is the same way guys have been tuning piggybacks for years. Stock ECU tuning is quite similar as well.
Fuel tuning with piggybacks has always seemed more difficult than with standalones just because the stock ECU and the piggyback sometimes fight. The stock ECU also has hundreds or thousands (GM) of parameters that affect the calculated injector pulse.
Tim
It seems like the initial setup should be fairly straightforward, yet the tuning process will be similar to many other piggybacks.
What this will likely mean-
You on a dyno with the dyno logging AFR
You logging parameters from the FIC
You logging parameters from the stock computer
You tuning the boost controller as all of this is going on (if used)
You will then have to take the data from these three/four sources, analyze it, and determine what changes to make to the FIC. This is the same way guys have been tuning piggybacks for years. Stock ECU tuning is quite similar as well.
Fuel tuning with piggybacks has always seemed more difficult than with standalones just because the stock ECU and the piggyback sometimes fight. The stock ECU also has hundreds or thousands (GM) of parameters that affect the calculated injector pulse.
Tim
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From: Calgary
Originally Posted by timg,May 30 2007, 05:22 PM
Fuel tuning with piggybacks has always seemed more difficult than with standalones just because the stock ECU and the piggyback sometimes fight. The stock ECU also has hundreds or thousands (GM) of parameters that affect the calculated injector pulse.
Tim
Tim
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From: EG
I'm no expert so hopefully someone with expertise can school me correctly if I'm wrong.
I didn't think any piggy back system can get around the "de-tune" during closed-loop unless it was intercepting and modifying the o2 feedback. No matter how much fuel you add or subtact, the o2 is going to get the AFR reading and send it back to ECU to "fix" it. And it will fix it in-accurately because its not using a Wideband o2.
During open-loop (WOT), most piggy back systems work fine.
I didn't think any piggy back system can get around the "de-tune" during closed-loop unless it was intercepting and modifying the o2 feedback. No matter how much fuel you add or subtact, the o2 is going to get the AFR reading and send it back to ECU to "fix" it. And it will fix it in-accurately because its not using a Wideband o2.
During open-loop (WOT), most piggy back systems work fine.
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From: Mesa
Originally Posted by elusiv,May 31 2007, 07:21 AM
I'm wondering, will the stock ECU and FIC have conflicts with each other? I realize it's been said that it will to a lesser extent, but does the FIC completely eliminate this problem or will we still encounter a bit of fighting between the two?
IF you change the injectors you need to scale them properly. For example if you take out the OEM 380cc injectors and install 600cc injectors, you would need to set all of your cells to -37 (dI=OEM/NEW-1) below the boosted range (</=0 psi). This should allow the PCM/ECU to properly control the car in closed loop operation since the F/IC will take the signal from the PCM/ECU and correct the pulse width for the larger injector. If scaled properly you should not have an issue.
If you make changes where the PCM/ECU could possibly be in closed loop (trying to manage A/F from O2 sensor feedback you could have conflicts between the F/IC and the PCM/ECU. For example if you use a VAFC/SAFC they simply modifiy feedback signals going to the PCM/ECU that cause it to think it is running richer, leaner, cooler, etc.. Eventually the PCM/ECU will catch on to your mischief and correct the problem itself.
If you want to use this to lean out an NA application for more power you will likely need to find out at what TPS level the PCM/ECU is forced into open loop and only make changes there. I am not sure what all conditions force the S2000 PCM/ECU into open loop. I know any MAP input above about -4in/hg will do it, and assume that TPS and a number of other sensor will do it also. For example - If you disconnect the primary O2 sensor the PCM/ECU will be locked into open loop (not optimal drivability and the idle Q sucks).
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From: Mesa
If you are considering this please go to the thread in the AEM forum and download the two documents at the top of the thread:
http://forum.aempower.com/forum/inde...c,19885.0.html
http://forum.aempower.com/forum/inde...c,19885.0.html
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From: AEM Electronics R&D
Originally Posted by WLAURENT,May 31 2007, 07:44 AM
If you are tuning in the boosted range (above 0 psi) the PCM/ECU will be in open loop and there should be no conflicts
IF you change the injectors you need to scale them properly. For example if you take out the OEM 380cc injectors and install 600cc injectors, you would need to set all of your cells to -37 (dI=OEM/NEW-1) below the boosted range (</=0 psi). This should allow the PCM/ECU to properly control the car in closed loop operation since the F/IC will take the signal from the PCM/ECU and correct the pulse width for the larger injector. If scaled properly you should not have an issue.
If you make changes where the PCM/ECU could possibly be in closed loop (trying to manage A/F from O2 sensor feedback you could have conflicts between the F/IC and the PCM/ECU. For example if you use a VAFC/SAFC they simply modifiy feedback signals going to the PCM/ECU that cause it to think it is running richer, leaner, cooler, etc.. Eventually the PCM/ECU will catch on to your mischief and correct the problem itself.
If you want to use this to lean out an NA application for more power you will likely need to find out at what TPS level the PCM/ECU is forced into open loop and only make changes there. I am not sure what all conditions force the S2000 PCM/ECU into open loop. I know any MAP input above about -4in/hg will do it, and assume that TPS and a number of other sensor will do it also. For example - If you disconnect the primary O2 sensor the PCM/ECU will be locked into open loop (not optimal drivability and the idle Q sucks).
IF you change the injectors you need to scale them properly. For example if you take out the OEM 380cc injectors and install 600cc injectors, you would need to set all of your cells to -37 (dI=OEM/NEW-1) below the boosted range (</=0 psi). This should allow the PCM/ECU to properly control the car in closed loop operation since the F/IC will take the signal from the PCM/ECU and correct the pulse width for the larger injector. If scaled properly you should not have an issue.
If you make changes where the PCM/ECU could possibly be in closed loop (trying to manage A/F from O2 sensor feedback you could have conflicts between the F/IC and the PCM/ECU. For example if you use a VAFC/SAFC they simply modifiy feedback signals going to the PCM/ECU that cause it to think it is running richer, leaner, cooler, etc.. Eventually the PCM/ECU will catch on to your mischief and correct the problem itself.
If you want to use this to lean out an NA application for more power you will likely need to find out at what TPS level the PCM/ECU is forced into open loop and only make changes there. I am not sure what all conditions force the S2000 PCM/ECU into open loop. I know any MAP input above about -4in/hg will do it, and assume that TPS and a number of other sensor will do it also. For example - If you disconnect the primary O2 sensor the PCM/ECU will be locked into open loop (not optimal drivability and the idle Q sucks).