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AEM EMS NA & FI Pros / Cons DBW cars

28 November 2009
The Drive By Wire AEM EMS offered by SOS.

I am curious on feedback from both NA and FI owners.

Pros and Cons.

Are there any complications when installing or is it as simple as plug in and map or is there more involved?

is there anything factory that doesn't work?

Because it is piggy backing the factory ecu is it completely in control? or does it switch over/trick the factory ecu?

Can you turn dash lights off with it? for example SRS because i installed harnesses.

Can you still pull error codes from the diagnostic port if required?

Will the car drive like it does on factory ecu or be problematic? assuming it's mapped by a professional.

I retains the factory Traction Control which is a bonus. Wahoo...

NA cars what typical gains are expected? Advantages and Disadvantages

FI cars is this worth the investment over an FIC? i doubt you install for performance reasons unless looking for big numbers as you have a turbo to make up those numbers so why would you install on a turbo car? i know it's better but why? reliability? map would be perfect instead of made to fit? any other advantages on a turbo car? any disadvantages? Could you run more boost safely?

Mapping wise would it take much longer to map compared to the FIC? i understand it is more involved as it controls more and more to setup.

How good is the AEM EMS in today's standards? i realize it's fairly old now and there is allot of competition.

Any other info worth mentioning?

Basically I am NA, I have ID injectors to be installed and an FIC however bhp gains will be very limited, if i went EMS i would get better gains and mapped better because other bolt ons, Some point i would like to go FI, perhaps near future so need to leave my options open installing something that would be a benefit rather than a pain when FI.

Lets just say i went with it, had it mapped with my bigger injectors. Then i had a turbo kit installed, can you drive the car carefully 100 odd miles to the tuner for a re-tune or is it a trailer job? keeping in mind it would already be mapped for the bigger injectors but not for FI.
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The last sentence is exactly where you need to be. Install the EMS with the boost mods. Injectors, 3bar MAP, etc. Tune it NA, and that will directly carry over to boost. Yes, you'll need boost tuning, but once the drivability is ironed-out NA, boost will tune-in, in just a few pulls.

And as hinted-at, it can be done remotely from my office desk.
Mind if I chime in with a question or two? I'm in the market for an NSX. I know myself, and know the "mod bug" will likely hit at some point during ownership, but am unsure whether to purchase an OBDI or OBDII vehicle due to this concern.

*Note some of these might not be exactly legal, from an Emissions Control standpoint (if this is against the rules here, please let me know.)

Questions below are in reference to the AEM EMS mentioned in the OP, and I assume as shown over @ SOS? -> http://www.scienceofspeed.com/produ...roducts/NSX/ScienceofSpeed/EMS_1995-2005_NSX/

1. Being plug-n-play in nature, and by retaining the OEM ECU (? - If I'm reading correctly), does this also imply that all OBD2 emissions controls are retained and would remain fully functional?

2. If the above is true - Does the AEM EMS allow "clamping" or "force ready" states for wideband & narrowband O2 sensors, speed sensors, etc. (I.E. - things that would usually cause a "fail" result during an emissions inspection.)

The only first hand experience I have with tuning solutions has been with Hondata's Flashpro for the 8th gen Civic Si's. Though not a "piggy-back" or standalone solution (as it manipulates the OEM ECU directly), it thankfully, has provisions to force a "ready" state for things like "presence of catalyst", "secondary O2 function / operation of catalyst", etc. and therefore, (even though I currently live in an emissions exempt county) has allowed me to keep the vehicle compliant with DMV standards throughout ownership.

Bottom line, if the possibility of passing emissions with a modified NA2 is only a thing we could wish for, then I want to ensure I know before I plunk a small fortune down on a car I've lusted after for quite some time now, and therefore will instead search for an NA1.
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My 1991 NSX was tested for emissions last year and flunked about as badly as any vehicle could flunk. It had an AEM EMS Series 1 installed, aftermarket headers and exhaust, SoS BBTB, Downforce Air Intake System, AEM A/F gauges on the driver A pillar, wide-band O2 sensors, but engine internals were stock. I took it to PTuning in Manassas, VA where troubleshooting revealed that the AEM EMS was no longer working (very unusual, but it did happen), along with some other issues. An AEM EMS Series 2 was installed (AEM fixed the Series 1 for $75 but I decided to upgrade), FiC 365cc injectors were installed, and Tuan at PTuning tuned the car on their steady-state dyno. I dropped about 2 rwhp, gained about 16 ft/lbs of torque (keep in mind that my baseline numbers were done on a different tuner's dyno), and the car passed emissions. An excellent tuner with a good dyno can do some amazing things...
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