I want to buy an Engine Management System for my Evo 9, and all I seem to hear about is the AEM EMS, but Ive also heard they have problems. Can someone elaborate or tell me there choice of EMS?

I went the other route, specifically a Haltech E11v2. The big problem with the Haltech is it does NOT provide tuning based upon knock using the stock knock sensor. Any tuning for knock must be done via wiring up the stock knock sensor in some custom fashion or using something like a J&S Safeguard system. The Haltech does provide anti-lag though. The AEM EMS is so well supported by so many tuners for the EVO that it's hard to say no to.

The BEST option is the factory ECU with proper tuning and logging tools..

Everything is a compromise.. Be honest with yourself about your intentions and how much time you want to spend with it.

my vote goes to the Autronic sm4.

The greddy emanage is pretty terrible. I had a friend with one and he ended up selling it. Stay away from piggybacks

stock - it has great knock protection, and i got mine for pretty cheap.

+1 for ecu

Depends on your application.

Sean

How about the HKS Fcon vpro?

I've been doing some reading about this system and it seems to have most/all of the features of a standalone but is used in conjunction with the stock ECU (which allows the possibility for inspection in states that use the OBDII port).

I know that a major downside is finding certified/trained dealers or tuners but this system seems to have a lot of positives.

Any comments?

P.S. I just came back to see that Sean Ivey had posted. I think he's an HKS certified guy. I'd like his comments as well as any others. Thanks.

~30,000?

+1 On stock ecu

I would ask yourself, what is it you are attempting to accomplish that can't be done with the ECU you already have? Once you have a list of your ECU's limitations that are currently holding you back, then use that as your shopping list for a new ECU.

IOW, if not having gear dependant boost control is holding you back, then that needs to be one of your selection criteria for a new ECU.

This is perfect since I'm more than likely going to be tuning my evo at your place...what would you rcommend since you deal with a lot of EMS?

+1 stock ECU

Keep the stock ecu unless you are planning on going crazy like +1000HP range. I have converted three cars back to stock ECU in the past month, and every one of them claimed it has never run better. Add the Tetra V5 flash and you are set!

What is your mods list like? What are you trying to do with the car? Track days? Drag racing? What size turbo...............

Sean

assuming you've outgrown the stock ecu, the Autronic SM4 PnP Board is a better unit but few people can tune it effectively. AEM is not as good but alot more tuners can set it up well for you.