AEM FIC, or EMU
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AEM FIC, or EMU
I'm looking at installing a turbo kit on my 05. I've got some experience building motors, supercharging, and tuning. Don't flame me but before I purchased the S2000 I built 700rwhp mustang.
Anyway, so I’m not an armature, by any means, both mechanically, and tuning wise.
Simple question, for a 8-10psi S2000 which piggyback should I go with. Which is currently the most popular. I'm leaning toward the FIC, but I've read some posts from the past that they have issues? I've also ready they have been fixed.
I really want to find a way to not spend the big money on a standalone. Everyone please chip in. Thanks
ps. oh, by the way.... after driving the S its almost funny, and sad how horribly engineered the mustang is. lol
Pete-
Anyway, so I’m not an armature, by any means, both mechanically, and tuning wise.
Simple question, for a 8-10psi S2000 which piggyback should I go with. Which is currently the most popular. I'm leaning toward the FIC, but I've read some posts from the past that they have issues? I've also ready they have been fixed.
I really want to find a way to not spend the big money on a standalone. Everyone please chip in. Thanks
ps. oh, by the way.... after driving the S its almost funny, and sad how horribly engineered the mustang is. lol
Pete-
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Isnt tunning from scratch a bitch tho? At least with a piggyback you have a starting point. All those honda engineers, and countless hours fine tunning the factory tune.
With a stand alone dont you have to completly start from scratch including all the part throttle crap. That could take years on the dyno, right? Or does the EMS come with some base tunes that are very close?
Pete-
With a stand alone dont you have to completly start from scratch including all the part throttle crap. That could take years on the dyno, right? Or does the EMS come with some base tunes that are very close?
Pete-
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Trustttt me. I have been through it.
I had an emu and it was garbage. I was going to go fic but I heard it's way to buggy and even with the software updates it's a pos. Just look for a used aem 1012. I've seen them go for 650 before. It's a night and day difference.
I had an emu and it was garbage. I was going to go fic but I heard it's way to buggy and even with the software updates it's a pos. Just look for a used aem 1012. I've seen them go for 650 before. It's a night and day difference.
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From: Nebraska
The AEM EMS has a pretty good base tune for a stock car that runs rich with conservative timing. The base tune is for an AP1 so keep that in mind as well.
You can buy a used AEM 1052 EMS for a couple hundred dollars more than a Greddy EMU and a 150 dollar boomslang harness for plug and play where as the AEM EMS 1052 is plug and play already. The 1012 EMS unit is pretty much the same thing as a 1052.
The EMU will tune what you're looking for, but I'd go for the EMS. With a piggyback, you'll be fighting the stock computer where as the EMS is the computer.
You can buy a used AEM 1052 EMS for a couple hundred dollars more than a Greddy EMU and a 150 dollar boomslang harness for plug and play where as the AEM EMS 1052 is plug and play already. The 1012 EMS unit is pretty much the same thing as a 1052.
The EMU will tune what you're looking for, but I'd go for the EMS. With a piggyback, you'll be fighting the stock computer where as the EMS is the computer.
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I'll see if I can find a used EMS around. The price of buying a new one scares me away.
Hey Evens Tunning, why do you need to monitor short term fuel trims? In part throttle situations don't the fuel trims automatical adjust (close loop through the ECU.
I thought a piggy back just cutts out the narrow band o2 ignals to the factory ecu when you go wot or possitive manifold pressure? Are you saying it cuts the narrow band signal to the ECU at all times? Please explain. I want to know what makes it quirky as people have said.
Or is the issue the factory ECU not being able to make part throttle short term fuel trims for larger injectors. A factory ECU has fuel trim gains that are set to a specific size injector in some cars. I could see that being an issue. I just want to know what makes them diffifcult to work with.
In my mustang I would actualy reflash the factory computer, and using tunning software similar to what the ford engineers used.
Hey Evens Tunning, why do you need to monitor short term fuel trims? In part throttle situations don't the fuel trims automatical adjust (close loop through the ECU.
I thought a piggy back just cutts out the narrow band o2 ignals to the factory ecu when you go wot or possitive manifold pressure? Are you saying it cuts the narrow band signal to the ECU at all times? Please explain. I want to know what makes it quirky as people have said.
Or is the issue the factory ECU not being able to make part throttle short term fuel trims for larger injectors. A factory ECU has fuel trim gains that are set to a specific size injector in some cars. I could see that being an issue. I just want to know what makes them diffifcult to work with.
In my mustang I would actualy reflash the factory computer, and using tunning software similar to what the ford engineers used.
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From: Huntsville, AL
Originally Posted by Evans Tuning,Feb 16 2010, 01:35 PM
I think a huge reason that the FI/C got a bad rap with running poorly is because the end user does not understand how it works properly. ..... There are also some other tricks that need to be applied to keep the vacuum/boost crossover point happy with fueling, but its all very basic and straight forward to do.
Greddy ULT also gets the same bad rap because people do not know how to use it.
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From: Maryland
Originally Posted by Evans Tuning,Feb 16 2010, 01:35 PM
The FI/C is different than most piggyback systems because it takes in the factory injector signal, and sends out a modified signal to the injector. Same goes with the cam/crank pick-ups to pull timing.
The stock ecu absolutely cannot control larger injectors without flooding out the car. The ecu is programmed with a set opening/closing time based on load and rpm (millisecond value). Since the ecu is fixed, and cannot be changed in terms of modifying the injector signal directly, the FI/C takes the factory millisecond value and decreases it by a specified %. That is how you can run much larger injectors and have the car run correctly.
To keep things simple the factory injector is a 360 cc/min. If you were to put in a 720 cc/min, to keep the engine at the same air/fuel ratio the millisecond value would have to be cut in half. If you were at 4 ms at 4,000 rpm to remain at 14.7:1, you would need to be at 2 ms with the new injectors. This is what the FI/C does with a load and rpm map with individual cell points for modification. You need to monitor short term fuel trims because if they vary more than +/- 3% the long term fuel trim changes, and the ecu will increase/decrease the millisecond value to get the air/fuel back into its correct range. That is a permanent change in the ecu output, unlike the short term which is a temporary change. The FI/C is based around the ecu sending out a consistent millisecond value for a given load/rpm point. If the long term trim changes, the FI/C will be off and driveability and a/f will suffer.
There is some other neat things you can do with the FI/C like clamp the MAP sensor voltage to not let it see boost, and pull ignition timing based on the same rpm/load point as the fuel mapping. You also have vtec point control based on load, rpm and tps input.
I think a huge reason that the FI/C got a bad rap with running poorly is because the end user does not understand how it works properly. You need to have a obd-2 scan tool to monitor short and long term fuel trims, and keep both as close to 0% as possible. There are also some other tricks that need to be applied to keep the vacuum/boost crossover point happy with fueling, but its all very basic and straight forward to do.
The stock ecu absolutely cannot control larger injectors without flooding out the car. The ecu is programmed with a set opening/closing time based on load and rpm (millisecond value). Since the ecu is fixed, and cannot be changed in terms of modifying the injector signal directly, the FI/C takes the factory millisecond value and decreases it by a specified %. That is how you can run much larger injectors and have the car run correctly.
To keep things simple the factory injector is a 360 cc/min. If you were to put in a 720 cc/min, to keep the engine at the same air/fuel ratio the millisecond value would have to be cut in half. If you were at 4 ms at 4,000 rpm to remain at 14.7:1, you would need to be at 2 ms with the new injectors. This is what the FI/C does with a load and rpm map with individual cell points for modification. You need to monitor short term fuel trims because if they vary more than +/- 3% the long term fuel trim changes, and the ecu will increase/decrease the millisecond value to get the air/fuel back into its correct range. That is a permanent change in the ecu output, unlike the short term which is a temporary change. The FI/C is based around the ecu sending out a consistent millisecond value for a given load/rpm point. If the long term trim changes, the FI/C will be off and driveability and a/f will suffer.
There is some other neat things you can do with the FI/C like clamp the MAP sensor voltage to not let it see boost, and pull ignition timing based on the same rpm/load point as the fuel mapping. You also have vtec point control based on load, rpm and tps input.
I think a huge reason that the FI/C got a bad rap with running poorly is because the end user does not understand how it works properly. You need to have a obd-2 scan tool to monitor short and long term fuel trims, and keep both as close to 0% as possible. There are also some other tricks that need to be applied to keep the vacuum/boost crossover point happy with fueling, but its all very basic and straight forward to do.
Does the user need to constantly adjust the fuel trims over time? or will they get to a point where they stabilize after a while?