Opinions on the AEM FIC/U and the CTSC

I have debated over what to do with my hi-boost whipple CTSC that sits sadly in my garage detached from my 99. I have an AEM standalone, 550 injectors as well. I had previously had the hi boost AEM system on my 92. I know that some of you boosters have used the AEM FIC/U with the CTSC. I understand the issues with using my AEM standalone with my Obd II car like loss of traction control. I was wondering if some of you could comment on your experiences with this AEM FIC/U CTSC setup. It has been awhile since I have seen any commentary on the longterm drivability, reliablility and performance of this system. Hope to be joining you in the boosted world!

Rod

The AEM stand alone will not work with an OBD2 car unless it is the MSL-AEM standalone which has been modified to work with the throttle by wire. I had the MSL-AEM unit in my turbo setup and it would stall whenever coming to a stop. Started fine and idled fine, just always stalled when decelerating. Always seemed to be running a little rich which may just have been a tuning issue. I have since switched to the FIC and the car runs perfectly, just ALOT more power, otherwise drives like stock. For OBD1, the AEM standalone, OBD2, AEM FIC.

Hi Rod

I don't know how the FIC compares to the AEM unit that I have. I know this unit worked well upon removal. This came off a 2004 NSX w/ a CTech SC. Here is the shameless plug:

http://www.nsxprime.com/forums/showthread.php?t=105031&highlight=boost

PM me if interested.

Jeff

I have a 91 running a hi-boost CTSC, I have set my car up with both the full stand alone AEM and the FIC, both are very good pieces, both have there plusses and both have there limitations.

The AEM ECU is the ultimate when it comes to tuning; the drawback is you must spend the time to make the tune perfect if you want it to drive like the OEM ECU under all conditions. The AEM ECU is a blank piece of paper you have a base map that will get the car started but that is about it, you can pay someone to get the car to a good working state and it will perform quite well but you should be willing to learn the software and understand basic tuning. Not that you will ever be doing the tuning yourself, until you get comfortable with that, but to allow you to gather the clues to the problems you are having and allow your tuner to use this information and the logs to solve any remaining issues. This takes time and you have to be willing to invest the time to perfect the tune.

The AEM FIC is a piggy back fuel and ignition modifier working with the OEM ECU to manage the engine. Designed for use with and OBD2 system it will still function quite well with OBD1 cars but it is a little harder to fine tune. Using a scan tool on an OBD2 car the FIC can be setup in one tuning session on the dyno and will require little if any time after that to get things running perfect. The reason the FIC is so much easier is that Honda already wrote the fuel and ignition tables for the un-boosted part of the tune, all you really need to be concerned with is the boosted sections of the tune. Since the difficult part of the tuning is done you just need to add a little safety to the existing tune and your done.

As I see it the FIC is the one for you, other than the fact that you already have the AEM ECU the cost to convert it over to OBD2 far out ways the cost of the FIC, the FIC will handle everything you are doing and if you have played with the old AEM ECU on your previous setup you will be amazed at how much easier this setup is to get going and to tune, buy the harness from Boomslang, install the injectors (you may need new ones to work with the newer OEM ECU, peak-hold vs. saturated will be the issue), Do the basic calculations to offset for the different size injectors and get it to a dyno, pull a little timing, dial in your fuel trims and WOT Air Fuel Ratios. That is about all it takes to tune this thing. I would add some gauges for that warm fuzzy feeling (fuel pressure, AFR, Boost). As far as drivability goes on my OBD1 car the FIC and the AEM ECU are very close, but I have about 100 hours in perfecting my tune for the ECU and about 5 for the tune in the FIC. There are things I like about the ECU, like having control of everything, but then again do you really need to have control over everything.

One little side note - if you are running the Autorotor I am not sure if this applies, but the Whipple hi-boost needs about 800-850 RPM at idle to keep from sounding like a bunch of bolts rolling around in a coffee can. When you run the FIC you will be stuck with the stock idle about 700 RPM. That may or may not bother you, but it is the one thing that I can tell you I miss from the AEM ECU, other than that the FIC has been a lot easier to live with and on the dyno I have seen little to no performance difference while in the boost.

Dave

Thank you Mister Dave!
I have new RC 440 injectors coming up along with the FIC and harness.
I have the old whipple and I have the 4.2,4.0 and 3.8 pulleys.
I have run all pulleys on my rebuilt slightly lower compression 3.0 91 engine with the old RRFPR.
I will probably go with the 3.8 for my set up being I'm at 2200' elevation and the aftermarket pistons.
Question is, how will the OEM ECU know what to do with the new 440 injectors?
Does it just learn from the stock 02 sensors that its pouring too much fuel into the engine?
Or is there something in the mapping of the FIC that I have to do to make my car run at non boost conditions.
Has anyone posted a DIY on this FIC for an OBD1 yet or do I send you and C-Speed chests of Gold to get the answers???
Thanks
Trev

Thanks guys for the great advice.

Sounds like the FIC is a great thing for OBD II cars. I think the use of the OEM ECU settings and having no loss in OEM function are huge advantages.Do any of you know whether or not there are any safety issues with the FIC because one doesn't have a standalone? For example, if the OEM ECU was not functioning properly, could that output cause the FIC to create a dangerous situation for the engine? Also, are the greater controls found on the AEM standalone of any significant benefit for a simple lower horsepower application like mine in terms of performance?

Hi Jeff, I still have my AEM-ECU in the garage as well.

Thanks for your help.

Rod

ffffanman said:

Thank you Mister Dave!
I have new RC 440 injectors coming up along with the FIC and harness.
I have the old whipple and I have the 4.2,4.0 and 3.8 pulleys.
I have run all pulleys on my rebuilt slightly lower compression 3.0 91 engine with the old RRFPR.
I will probably go with the 3.8 for my set up being I'm at 2200' elevation and the aftermarket pistons.
Question is, how will the OEM ECU know what to do with the new 440 injectors?
Does it just learn from the stock 02 sensors that its pouring too much fuel into the engine?
Or is there something in the mapping of the FIC that I have to do to make my car run at non boost conditions.
Has anyone posted a DIY on this FIC for an OBD1 yet or do I send you and C-Speed chests of Gold to get the answers???
Thanks
Trev

Click to expand...

Trev. If you can get me the briefcase from pulp fiction I can tell you .

Basically , the FI/C will modify the signals that the oem ecu sees , thereby causing the ecu to change it's output , it is an input / output box , VERY simple and works great.

TECHNICALLY SPEAKING ,it works best with OBDII , since you can watch the fuel trims and timing on a scan tool , with OBDI you need to do some math and use a timing light on the dyno to establish settings.

I would never say that tuning an fic or ems is exactly what I would describe as DIY.

ALSO , we have found that the fic works best with injectors lees than double the stock injectors , so you are on the right track with 440's , now just get some methanol before you really make a mess of things!

Rod,
The stock AEM standalone will not recognize the throttle by wire setup of the OBD2 car. Withe OBD2, the only option is the MSL-AEM like Jeff or the FIC. Do a search of the MSL-AEM and you may see some others experience. MASE posted some interesting information.
Tim

HotRod said:

Thanks guys for the great advice.

Sounds like the FIC is a great thing for OBD II cars. I think the use of the OEM ECU settings and having no loss in OEM function are huge advantages.Do any of you know whether or not there are any safety issues with the FIC because one doesn't have a standalone? For example, if the OEM ECU was not functioning properly, could that output cause the FIC to create a dangerous situation for the engine? Also, are the greater controls found on the AEM standalone of any significant benefit for a simple lower horsepower application like mine in terms of performance?

Hi Jeff, I still have my AEM-ECU in the garage as well.

Thanks for your help.

Rod

Click to expand...

Hi Rod

As jorligan stated, the AEM I have is specific for OBDII cars and so is the harness. I didn't run this in my 92'. It's a long story as far as how I acquired it but I know it worked well upon removal...was removed because previous owner sold the car/SC setup.

Jeff

I have been running the Tec-3 from Electromotive and it is perfect with the TBW. Runs, starts and ideals like stock. What ever you go with just make sure you have a tuner in your area.

angus said:

Basically , the FI/C will modify the signals that the oem ecu sees , thereby causing the ecu to change it's output , it is an input / output box , VERY simple and works great.

Click to expand...

Please no disrespect is meant to Angus, and I hope he understands my desire to clearify the statement he made.

I think this may be a little misleading, as I understand it based on the connecting the FIC to the ECU, the ECU is seeing a modified MAP sensor Voltage (voltage clamp only for boosted part of map) and if you wire in the O2 sensors that signal will be modified as well. Then the OEM ECU will dictate a Fuel pulse and Ignition timing for the given conditions it sees. After the OEM ECU issues its commands the AEM FIC will modify those outputs from the ECU following the tables programmed in the FIC and send them to the injectors and timing control of the engine. The tables in the FIC will be altering the output of the ECU not the input to the ECU. May be a little nit picking but I wanted to make sure to be clear.

The FIC also sports it own MAP sensor so when the stock sensor could potentially run out of room as the boost is increased the FIC will manage the modifications to the fuel and timing tables using a known reference from its own MAP sensor, all the while the OEM ECU is supplied a voltage clamp on the stock MAP input and feed a constant value as close as possible to the WOT value, the ECU thinks it is in open loop WOT and follows the preprogrammed Honda table for WOT, the FIC then modifies those output signals to change the Fuel and Timing to match the tables in the FIC.

These are the basic functions for the FIC, but it can do more. It can operate a boost controller, log sensors, offset for larger injectors, offset the O2 signals to lower or raise the closed loop AFR, and with some creativity there are more things that can be done like maybe even idle control? (I will be looking into that a little closer)

The biggest limitation to its use with the CTSC or at least the Whipple CTSC is not being able to command an idle RPM, I just do not like hearing the blower lash on idle, and having an idle around 850 RPMs does not bother me a bit and solves that issue completely.

This leads me to a question. Does anyone know if any of the Chip ECU programmers have found the idle set value, maybe it would be a simple as using a modified chip like the Dali or others and have the chip burned with a higher idle value.

Starting to ramble,

Dave

Keep rambling, I like it!
Sending a message to Brian at Prospeed to jump in about the idle.
Thanks! One gold brick being sent out today.
Trev

DDozier said:

Please no disrespect is meant to Angus, and I hope he understands my desire to clearify the statement he made.

I think this may be a little misleading, as I understand it based on the connecting the FIC to the ECU, the ECU is seeing a modified MAP sensor Voltage (voltage clamp only for boosted part of map) and if you wire in the O2 sensors that signal will be modified as well. Then the OEM ECU will dictate a Fuel pulse and Ignition timing for the given conditions it sees. After the OEM ECU issues its commands the AEM FIC will modify those outputs from the ECU following the tables programmed in the FIC and send them to the injectors and timing control of the engine. The tables in the FIC will be altering the output of the ECU not the input to the ECU. May be a little nit picking but I wanted to make sure to be clear.

The FIC also sports it own MAP sensor so when the stock sensor could potentially run out of room as the boost is increased the FIC will manage the modifications to the fuel and timing tables using a known reference from its own MAP sensor, all the while the OEM ECU is supplied a voltage clamp on the stock MAP input and feed a constant value as close as possible to the WOT value, the ECU thinks it is in open loop WOT and follows the preprogrammed Honda table for WOT, the FIC then modifies those output signals to change the Fuel and Timing to match the tables in the FIC.

These are the basic functions for the FIC, but it can do more. It can operate a boost controller, log sensors, offset for larger injectors, offset the O2 signals to lower or raise the closed loop AFR, and with some creativity there are more things that can be done like maybe even idle control? (I will be looking into that a little closer)

The biggest limitation to its use with the CTSC or at least the Whipple CTSC is not being able to command an idle RPM, I just do not like hearing the blower lash on idle, and having an idle around 850 RPMs does not bother me a bit and solves that issue completely.

This leads me to a question. Does anyone know if any of the Chip ECU programmers have found the idle set value, maybe it would be a simple as using a modified chip like the Dali or others and have the chip burned with a higher idle value.

Starting to ramble,

Dave

Click to expand...

Dave , no offense taken here ,actually we are both correct, I said that the fic is an input/output box , was trying to keep it simple ,actually it mods both inpt and output signals, that is how it keeps your MIL from coming on , but yes , you are correct about how it will modify the injector signal after the ecu , timing too . The signals for map, o2s, vtec pressure etc. are modified before they reach the ecu.

I've tested The AEM FIC on a customer NSX on the dyno with great results. However the there isn't a way to control the idle. There isn't a way to control idle yet on the ecu side. I've looked for a idle value on the rom but it looks like it's controlled by the ecu not the rom unlike the other Honda Ecu's. There really isn't much you can do except trying to adjust the fuel values to keep it idling or the old school way we used to do it on the B, D, and H series engines and that is to adjust the idle air screw on the throttle body to raise the idle. Sorry I couldn't be more helpful Trev!

Thanks for the input. So just to clarify, you guys think that the CTSC with the AEM FIC/U would be safe with no AFR problems only a clinky idling noise.

Rod

HotRod said:

Thanks for the input. So just to clarify, you guys think that the CTSC with the AEM FIC/U would be safe with no AFR problems only a clinky idling noise.

Rod

Click to expand...

Yes! :smile:

And no black bumper because of rich A/F associated with the high boost CTSC.

The F/IC offers direct injector control (it doesn't modify the MAP or O2 signals into the ECU like other products - VAFC for example) allowing increased or decreased injectory duty cycle. The F/IC also offers ignition control by intercepting and retarding ignition.

We've used this on many cars in the 300-500 hp range and include it as the standard tuning solution for our supercharger kit:
http://www.scienceofspeed.com/products/engine_performance_products/NSX/ScienceofSpeed/supercharger/

You can find more info on this and the wiring harness here:
http://www.scienceofspeed.com/products/engine_performance_products/NSX/AEM/FIC/

thank you,
-- Chris

On my car personal (93 OBDI) I use AEM EMS of course, I outfitted a customer's 2000 with a F/IC and had it tuned. Car ran great. Didn't have a stall issue, the wiring is per injector and the cam and crk sensor.

Like what chris said, other piggy backs will try the ecu by altering the map/maf signal and add fuel like that. The FI/C actually controls the injectors.

IIRC Wasn't there a harness that bundled the stock ecu and the EMS together using the stock computer for Drive by wire?

Chris@SoS said:

The F/IC offers direct injector control (it doesn't modify the MAP or O2 signals into the ECU like other products - VAFC for example) allowing increased or decreased injectory duty cycle. The F/IC also offers ignition control by intercepting and retarding ignition.

-- Chris

Click to expand...

Again not trying to be nit picky but, the FIC can alter the O2 singnal to the OEM ECU if you wire the O2 Sensors per the instructions and change the values in the O2 offset tables, this step is not used by all tuners and really is only used to over ride the AFR while the ECU is in closed loop. Changes made in this table will effect the O2 sensor voltage that the OEM ECU is seeing from the stock O2 sensors and trick it into thinking the the car is running stoich but it can be richer or leaner if you wanted, these changes only take effect while the OEM ECU is in closed loop once you put it under a load the OEM ECU will go Open loop and the O2 information is ignored. This is one area that I am playing with to offset the Idle AFR combined with Idle timing to try to reduce blower lash at idle, it seems to be helping a little but not as good as raising the Idle.

The MAF or MAP table can be used to modify the MAP sensor inout to the OEM ECU, but in the case of the NSX it is not used this way. For the most part the only changes made to the MAP sensor voltage being feed to the OEM ECU is to act as a voltage clamp to prevent the OEM ECU from ever seeing a value that it does not understand, that would be any value that represents boost. Without this modification to the MAP sensor input on the OEM ECU you would force the ECU into limp mode and the CEL would be displayed on the dash.

Just trying to be clear about how this thing works. May be more than you guys want to know but the software that you download from AEM to run the FIC includes a reasonable description of what all the FIC can do, just not so much on how to do it.

http://forum.aempower.com/forum/index.php/topic,22476.0.html

Dave

Prospeed said:

I've tested The AEM FIC on a customer NSX on the dyno with great results. However the there isn't a way to control the idle. There isn't a way to control idle yet on the ecu side. I've looked for a idle value on the rom but it looks like it's controlled by the ecu not the rom unlike the other Honda Ecu's. There really isn't much you can do except trying to adjust the fuel values to keep it idling or the old school way we used to do it on the B, D, and H series engines and that is to adjust the idle air screw on the throttle body to raise the idle. Sorry I couldn't be more helpful Trev!

Click to expand...

Thanks good to know, just have to keep playing with it, if you raise the idle air I think that can cause a CEL if the Idle air bypass is out of range as the ECU tries to remove air to control idle. Not sure how much you can change there either, Have you guys had any luck in bumping the idle up on a NSX to say 800-900 RPM.

Dave

DDozier said:

Thanks good to know, just have to keep playing with it, if you raise the idle air I think that can cause a CEL if the Idle air bypass is out of range as the ECU tries to remove air to control idle. Not sure how much you can change there either, Have you guys had any luck in bumping the idle up on a NSX to say 800-900 RPM.

Dave

Click to expand...

I have done it many times before on other Hondas with no problems. Racing the idle on the throttle body will not throw a CEL. At least I have never see that before in 12 years of working on them. Give it a try! :smile:

Thanks guys! Sounds like the AEM F/ICU is going to be the ticket for me! Thanks for the input.

Rod

Bumping an old thread if ya'll don't mind. I've decided to dive head first into fine tuning my own FIC in my ODB1 91. I'll likely get a base tune done first with Bisimoto locally but my gut tells me it will take me hours and hours of fine tuning to get it running optimally.

Have some questions:

1. How does the F/IC compensate for altitude at say 6000ft? Dave mentioned it has it's own MAP sensor. Is that built-in the F/IC case or is that an external sensor to measure manifold pressure, say at boost? I've read other Honda ECUs have a built in barometer inside the case but not sure if the NSX does. I'd be surprised if it didn't. At wide open throttle on a stock ECU the ECU reads not the boost pressure in the manifold, but the pressure in the ECU case at altitude advances the ignition and leans the fuel. This is not what you want in a boosted car if you want reliability. This is my current working assumption so i'm a bit confused how to tune for this.

2. I've read that there may be a 2D and a 3D method for controlling a Meth kit. Has anyone had success with using perhaps Boost and IAT to trigger? Or perhaps a 0-5V progressive trigger so the spray can be controlled gradually? I've read some installations where the Meth is ON as soon as the F/IC sees boost. Just looking for a more robust 3D method of controlling the Meth. (Actually i'll be using 80/20 so it'll likely be mostly water)

3. It seems the common assumption with the base CTSC tune (RRFPR, boost-a-pump, etc) is that it relies on the factory ECU to retard the timing, richens fuel when IATs get high. Is there a way to "undo" this with the F/IC? It seems during normal driving conditions (unboosted) my IATs hover around 100-140degs. I'm assuming at these temps the ECU isn't retarding timing nor richening fuel. With Meth/Water it seems the best we can cool these CTSCs is around 160degs and at this temp any more spray yields diminishing cooling results. My assumption is at 160 (likely 180+ at the track) the factory ECU will still pull timing and run fuel fat. Just trying to conceptualize how the F/IC can compensate against this condition...

4. Lastly, might be a dumb question, but the F/IC doesn't requires an input from a Wideband O2, right, but is it optional? If a UEGO was added into the system can the F/IC make dynamic adjustments based on the AFR at that point in time? It was mentioned earlier the the FIC can intercept the O2 signals as well. I'm assuming that's the factory narrowband O2 yes?

Thanks much for any input. Hope to return the favor someday!

Ryu,

If you haven't posted there yet try the AEM message board/support forums. They are pretty good at getting back on questions.