For those of you who have any questions related to the AEM EMS I am offering our tuner Sean McElderry up for assistance to this forum. He is arguably the best AEM tuner in the world and can greatly assist you with any problems you might have.
We work in conjunction with AEM to promote their products and have installed AEM EMs's in our customers' Supra's / Civics / Eclipses / MR2's / S2000's / 3000GTs and RX7's for the past 2 years.
For those that are considering getting an AEM EMS for your NSX, let me list off some of the key selling points....
1) Auto-mapping... With this, you program in the target A:F based on engine rpm and load. We will typically program in around 11.5:1 under WOT situations, 14:1 on idle and 16:1 to 17:1 on cruise for economy reasons. Then you drive around and the cells in fuel map table will slowly change as you pass through them a few times until they get to the desired A:F ratio. We don't usually use this feature because it doesn't work as flawlessly as some of the other standalones out there, but it does work quite a bit better than it used to. I also don't like to do it because I don't like to take the chance of the computer doing something I don't want it to.
2) O2 Feedback.... We first tune the car with O2 feedback turned off. We do this by adjusting the values in the fuel map. We also use boost compensation (which I'll explain later) which makes this much easier. Once we're pretty close, we'll program the O2 feedback table with the target A:F ratios. Now when you're driving around, the computer is always using your fuel map but at the same it is doing on the fly adjustments to the fuel map based on your feedback settings towards your goal.
3) Boost Fuel Compensation.... We use boost compensation (especially on turbo'd and supercharged cars) to add or subtract from our fuel map. When using boost compensation, the fuel map ends up looking exactly like a torque curve with the peak fuel setting corresponding to the peak torque value. Then much of the fuel map has the same values all the way up and down (on the load axis). This makes it really easy to tune and allows for nearly perfect A:F ratios in all gears.
4) Knock and Timing.... Another thing the AEM does that is fantastic is it will allow you to program your own knock noise table based on engine rpm. There are a lot of things that make vibrations that the computer picks up as knock. Some might be real detonation, but a lot of the noise is simply shifting gears, a turbo wastegate opening, etc. etc. What we'll typically do is run some good gas like C-16 race fuel and leave the timing somewhat conservative. We'll then datalog the knock sensors. Once we have the raw knock values for the car, we'll modify the knock noise table to be right above these values. This tells the computer if you ever see a knock sensor voltage above this amount then it's probably detonation. Now we can program what to do if indeed we do see knock. #1 we pull out timing. You can program how much timing to pull out and how long and how fast to put it back in. You can also program a certain percentage of fuel to inject. Detonation can often be eliminated by injecting extra fuel. Once these are set, we can start advancing the timing to increase power until we do see some knock. then we can back it off a bit.
5) 2-step.... The AEM also has a built in 2-step where you can program it to not only pull spark, but pull timing as well. This 2-step can greatly increase your 60 fts. With boosted cars we've seen as much as 22psi built on the line.
6) Injector Duty Cycle.... One thing that we take very seriously is never running lean under WOT conditions. The AEM shows your injector duty cycle all the time. It allows you to make cylinder to cylinder fuel trim adjustments as well as overall fuel adjustments. We datalog the injector duty cycle and when you get past 80% injector duty cycle we typically recommend running larger injectors. On my personal car we went from 550cc injectors to 720cc to 850cc to 1000cc and we ended up hitting 85% injector duty cycle at 70psi of fuel pressure so now I have 1200cc injectors in it.
7) Boost Control.... If you are running turbos you'll never need another boost controller. You simply program in the w/g duty table and turn w/g feedback on and it will allow you to control boost perfectly through the AEM. You can also advance timing quite a bit in the turbo spool up area to reduce turbo lag.
8) Traction Control.... The newest version of the software now has traction control. It will pull out spark when traction is lost to maintain traction. If you do have turbos you can use speed based boost control to also prevent wheel spin.
Sean will be following this thread and will answer any questions that you may have with your EMS or any tuning related questions.
Take care,
Chris.
We work in conjunction with AEM to promote their products and have installed AEM EMs's in our customers' Supra's / Civics / Eclipses / MR2's / S2000's / 3000GTs and RX7's for the past 2 years.
For those that are considering getting an AEM EMS for your NSX, let me list off some of the key selling points....
1) Auto-mapping... With this, you program in the target A:F based on engine rpm and load. We will typically program in around 11.5:1 under WOT situations, 14:1 on idle and 16:1 to 17:1 on cruise for economy reasons. Then you drive around and the cells in fuel map table will slowly change as you pass through them a few times until they get to the desired A:F ratio. We don't usually use this feature because it doesn't work as flawlessly as some of the other standalones out there, but it does work quite a bit better than it used to. I also don't like to do it because I don't like to take the chance of the computer doing something I don't want it to.
2) O2 Feedback.... We first tune the car with O2 feedback turned off. We do this by adjusting the values in the fuel map. We also use boost compensation (which I'll explain later) which makes this much easier. Once we're pretty close, we'll program the O2 feedback table with the target A:F ratios. Now when you're driving around, the computer is always using your fuel map but at the same it is doing on the fly adjustments to the fuel map based on your feedback settings towards your goal.
3) Boost Fuel Compensation.... We use boost compensation (especially on turbo'd and supercharged cars) to add or subtract from our fuel map. When using boost compensation, the fuel map ends up looking exactly like a torque curve with the peak fuel setting corresponding to the peak torque value. Then much of the fuel map has the same values all the way up and down (on the load axis). This makes it really easy to tune and allows for nearly perfect A:F ratios in all gears.
4) Knock and Timing.... Another thing the AEM does that is fantastic is it will allow you to program your own knock noise table based on engine rpm. There are a lot of things that make vibrations that the computer picks up as knock. Some might be real detonation, but a lot of the noise is simply shifting gears, a turbo wastegate opening, etc. etc. What we'll typically do is run some good gas like C-16 race fuel and leave the timing somewhat conservative. We'll then datalog the knock sensors. Once we have the raw knock values for the car, we'll modify the knock noise table to be right above these values. This tells the computer if you ever see a knock sensor voltage above this amount then it's probably detonation. Now we can program what to do if indeed we do see knock. #1 we pull out timing. You can program how much timing to pull out and how long and how fast to put it back in. You can also program a certain percentage of fuel to inject. Detonation can often be eliminated by injecting extra fuel. Once these are set, we can start advancing the timing to increase power until we do see some knock. then we can back it off a bit.
5) 2-step.... The AEM also has a built in 2-step where you can program it to not only pull spark, but pull timing as well. This 2-step can greatly increase your 60 fts. With boosted cars we've seen as much as 22psi built on the line.
6) Injector Duty Cycle.... One thing that we take very seriously is never running lean under WOT conditions. The AEM shows your injector duty cycle all the time. It allows you to make cylinder to cylinder fuel trim adjustments as well as overall fuel adjustments. We datalog the injector duty cycle and when you get past 80% injector duty cycle we typically recommend running larger injectors. On my personal car we went from 550cc injectors to 720cc to 850cc to 1000cc and we ended up hitting 85% injector duty cycle at 70psi of fuel pressure so now I have 1200cc injectors in it.
7) Boost Control.... If you are running turbos you'll never need another boost controller. You simply program in the w/g duty table and turn w/g feedback on and it will allow you to control boost perfectly through the AEM. You can also advance timing quite a bit in the turbo spool up area to reduce turbo lag.
8) Traction Control.... The newest version of the software now has traction control. It will pull out spark when traction is lost to maintain traction. If you do have turbos you can use speed based boost control to also prevent wheel spin.
Sean will be following this thread and will answer any questions that you may have with your EMS or any tuning related questions.
Take care,
Chris.
Your shop is looking great! 
Are you looking to work with some of the current boosted cars out there? Work with current FI vendors who are not as familiar with the AEM? Other?
