The best ECU choice is - to post here!
This is about the quest to find the most suitable and potent ECU from the US Evo 8, four plug versions, that is available for flashing, tuning and playing.
I identified 3 USDM ECU P/Ns:

• A) E8.03 - 4Plug MN132874
• B) E8.04 - 4Plug MN191022
• C) E8.05 - 4Plug 1860A118

1. Are these all the same internals, same capacity, same limits? Just different P/Ns?
2. Differences in reliability, why?
3. Differences in tunabilty, which values and how much?
4. Differences in processor speeds, how much difference?
5. Differences in boards, what's the effect?

If 1. is true I would see my best buy in C) for it being the "youngst" one. Not?
Do I need to flash the Mitsu prescripted ROM updates prior to the Tephra and ROM versions I want to finally use?

Background: An USDM E8 4 plug ECU into my E6 JDM. My E6RS receives ongoing mods and it's time for an ECU that does map switch, launch control and other greats. But that's just me. I know that your appreciated answers will not just help myself. And it is absolutely amazing how much knowledge is "in here"! But enough honey now - still, keep up guys!

Cheers & THY!
Kris
My wheels: CP9A RS very late 1999, JDM converted LHD, no AYC, 5 speed, no A/C, plenty more no..., like e.g. no power windows, no extra weight

 

Why you are not happy with Ceddy mods?
There is no big differences between '03 and '04 ECUs (ROM files), but '05 is a little bit different, as USDM '05 has ACD, so '05 ROM is different (more memory is used because of ACD). I would recommend to use 03/04 ECU with 90550001 (Ralliart) ROM file. 90550001 may also be used (works well) in Evo VI.

 

ACD has nothing to do with ecu memory, all evo 7/8 roms are 256k. I have friend using 9653 sd rom with e8 ecu in evo 6 and it works perfectly, it is all about how you set it up. With 9055 you might gain some trouble codes like rear O2 but those are easy to handle anyway.

My opinion to question should one use e8 ecu in older evo is that after trying and then actively used livemapping I would anyday go with e8 ecu only because of possibility to use livemapping in tuning, all other stuff like sd and great support here at evom for e8 roms is just bonus

 

Several years ago, maybe in 2007 or something there were no tephra mods for '05 ECU and there was an opinion, that there is no memory left in the ROM for that...
First link search gave me: https://www.evolutionm.net/forums/ec...-usdm-ecu.html

 

use the 6 ecu with ceddy rom it has launch control /map switching /cel on knock etc

look here

www.geekmapped.com

 

Can't be better Still waiting for the anwer, why owner wants Evo VIII ECU swap.

 

no egr / no wiring swaps / no throttle hang and retain sas gotta be a bonus

 

Yes, I remember there was some rom with memory filled and my reference to rom size was incorrect as it has nothing to do with that, sorry. Anyway you can criss cross evo 7 and 8 roms and acd still works (remember that in JDM models acd was already at evo 7) so I would still say acd has nothing to do with that memory usage.

Why someone wants evo 8 ecu? I understand OP, like I said I would do the same anyday only because of livemapping

 

I would like to profit from most advantages and more or less easy access to tuning. It is a lot easier for me to find sufficient info on the USDM E8 than on the 6 ECU. It's a combination of SW and HW mods. Say auto ICS, switch maps, valet mode, live tuning, logging, NLTS and more to come. If all that is doable likely E6/E8 fine. I would still need the information then...
Else, the only restriction I see in so far in stock ECU is the scalability when going 1.7bar w/ 1000cc. But that would be an E7 RA ECU then.

Thanks for sharing and input so far.
Kris

 

You are welcome. Although I can't see any problems with stock ECU if you want to run higher boost ant use bigger injectors. You can rescal your maps or even use BIG maps (Ceddy mod). Correct me if I'm wrong.

 

Yes, some (I have tested few myself) Evo VII rom files work on USDM 4 plug ECUs ECU hardware is compatible.

 

Uh, it's been a while, ceddymods. I didn't remember til just now! Will look into it again now. Seems a lot covered there from the mainpage.
Geeks denied access - reasons unknown, no reply to personal e-mail.

Thanks Todd

 

yeah they are flash combatible

 

Rescaling cc no issue, boost may be issue, kinda hard to find comprehensive and precise data (i.e. hold/peak) in something like a comparison chart.
but again, RA from E7 is another option and maybe another thread.

 

I had fuel/ignition maps rescaling in my mind Same thing that guys are doing for any other stock (260 load) maps for years.