There appear to be 3 versions of the JM8859 EVO 9 (north american market) ECU.

JM88590-13 original release
JM88590-14 first revision
JM88590-15 second revision

There has been a lot of discussion lately that EVO 9 cars produced later on in the model run are not registering stock dyno numbers or running trap speeds as high as the early run cars.

I purchased my 9 in July and it had the latest (15) software loaded.

So, out of curiosity, I downloaded the version 13 and 14 maps. I did a quick check of the high octane timing 1 and 2 tables as well as the high octane fuel table and compared the maps to each other. As far as I can tell those specific tables are the same across the board. But when comparing the 13 and 14 maps to the stock 15 map loaded in my ECU via ECUFlash, there are differences. I haven't yet documented them, however.

Right now I am running the 13 map. My car feels a little quicker and boost seems to spike a little higher, but it's all very subjective and the butt dyno is a known liar. I'm going to hopefully sit down and compare all the values between all three maps tonight to see if I can find what Mitsu changed from version to version. That is if someone hasn't done so already. But I searched and haven't found any posts from anyone saying they have.

 

subscribed... I'd very much like to know this also. I bought one of the early 9's I believe (nov or dec 05) so I would assume I have the release 13.

Anyway good work! Hopefully others chime in!

 

Very interesting stuff. Id like to find out about this as well. Really should buy my Tactrix cable so I can use EvoScan and ECUflash to look at stuff. I bought my IX in January of 06. Ive since had it tuned by Shiv so I dont plan on changing anything. Mainly just curious about the differences.

 

me too.. im custom flashed and dont want to change anything unless the updates are necessary to the life of the engine...

 

IF you are already flashed you already surpassing what the stock map (13-15) would be anyway. This makes lots of sense, as I have a 11/05 IX MR that from teh factory made 23psi at peak torque stock.

 

I heard there was some other updates though besides just fuel and timing..

 

it seems the new cars are making alot lower tq due to less boost. some new cars are only doing 210-220 wtq when the older ones were doing 23X tq at the wheel.

 

hmm...very interesting. subscribed!

 

Stock spec is 20.3psi, perhaps they had some early spike issues and corrected that with some revisions. Even still it should all pretty much average out to a very small time difference in terms of 0-60, 1/4, etc.

 

I have had similar results with my 03 EVO. I bought my EVO in FEB '04 so I know it was not part of the first allocation.

Oringially, my EVO had many problems with the random p0300 problems, but after loading a stock 1st allocation ROM the p0300 problem has been reduced alot, at the cost of a hyper sensative fuel cut that was quickly tuned out by adjusting the boost limits.

 

The verdict is in. After comparing all the tables of the 13-15 ROMs they're almost completely identical. There was one field that ECUFlash could not read on the version 13 ROM - but it did return a value on the version 14 and 15 ROMs and they were identical. The field that could not be read for the version 13 ROM was Injector Size Scaling..

See attached spreadsheet.

 

which is a problem I also have, no injector scaling for some reason. So I need the XML for 14 to correct that right?

 

how about the wastegate solenoids? Since they're unreadable, maybe there's some differences in those fields?

 

Possibly, but since they're unreadable on all 3 maps it's tough to say.

 

Try downloading the 14 or 15 base maps and updating your ECU with them..