How do I know which ECU upgrade kit to get?
How do I know which ECU kit to get?
For example AEM, Apexi AFC or Exede, is there a big difference? Arent they suppose to work the same and why is the AEM much more expensive than the rest?
Last edited by Derek888; Oct 10, 2004 at 08:18 AM.
Whoa! There's a great deal of difference in the list you have and not just in price. Start looking for threads on these things (there's lots of them) and read what the manufacturers say too. Search (here) and google (other sites) are your friends. 
There are plenty of people on this board that know way more than I do about these tuning devices but I think I can give you some basics:
The AEM is a standalone device. It replaces the stock ECU altogether so obviously it controls everything and is completely customizable. This is both its strength (you can do whatever you want) and its weakness (you have to do all the mundane things like AC, idle, etc.) Given a good tuner you can do anything you want and from what I've been told retain stock drivability.
The Xede is a piggyback device. It works with the stock ECU modifying parameters to change the tuning. This lets the ECU do the mundane things and have the piggyback "take over" at other points. Some piggybacks also can drive certain functions directly (like the UTEC) but in general they are not quite as flexible as a full standalone since the stock ECU has to be kept happy. Again, given a good tuner you can do nearly anything.
The AFC also works with the stock ECU, but if I am not mistaken it can only control fuel and not timing. So, it is much more limited than the Xede. Given a good tuner you can do alot, but that same good tuner could do more with the other options.
There are plenty of people on this board that know way more than I do about these tuning devices but I think I can give you some basics:
The AEM is a standalone device. It replaces the stock ECU altogether so obviously it controls everything and is completely customizable. This is both its strength (you can do whatever you want) and its weakness (you have to do all the mundane things like AC, idle, etc.) Given a good tuner you can do anything you want and from what I've been told retain stock drivability.
The Xede is a piggyback device. It works with the stock ECU modifying parameters to change the tuning. This lets the ECU do the mundane things and have the piggyback "take over" at other points. Some piggybacks also can drive certain functions directly (like the UTEC) but in general they are not quite as flexible as a full standalone since the stock ECU has to be kept happy. Again, given a good tuner you can do nearly anything.
The AFC also works with the stock ECU, but if I am not mistaken it can only control fuel and not timing. So, it is much more limited than the Xede. Given a good tuner you can do alot, but that same good tuner could do more with the other options.
SAFCII is cheap and gets the job done. If you only want BPU(3" turboback, mbc and filter) then I would recommend this. Also recommend the available Flashes too.
UTEC/XEDE do about the same and have timing control and cost about the same. If you want more then just BPU for example: if your going to upgrade fuel system, intercooler, cams and so forth, this is the route.
AEM EMS replaces your ECU and has full control. If you want all out performance with huge upgraded turbo this is the route. Just having the AEM alone on a stock EVO with dyno tuning averages about 300+awhp/tq, none the above SAFCII/UTEC/XEDE can do this.
UTEC/XEDE do about the same and have timing control and cost about the same. If you want more then just BPU for example: if your going to upgrade fuel system, intercooler, cams and so forth, this is the route.
AEM EMS replaces your ECU and has full control. If you want all out performance with huge upgraded turbo this is the route. Just having the AEM alone on a stock EVO with dyno tuning averages about 300+awhp/tq, none the above SAFCII/UTEC/XEDE can do this.
