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EVO 7.5 GT-A, anyone with experience?

PostPosted: Sun Apr 13, 2008 6:46 pm
by Mattjin
Hi everyone,

I am quite experienced with tuning aftermarket ECU's, but this is my first attempt and reflashing. Anyway, the car is a 2002 JDM EVO 7 GT-A and I have grabbed the ROM out of the ECU without a problem.

Trouble is, what the hell do I do with the scrambled load and rpm values? Maps look fine but the scales are just garbage. From what I have been reading on here there is something called an XML file that seems to control these things, but how do you go about setting it up?
It uses 80700010 from what I can gather.

Map attached

PostPosted: Mon Apr 14, 2008 4:01 am
by Mattjin
It's OK, I figured it out.

All of the data endians were set to "little". Changed them to "big" and everything reads correctly. Amazing what you can do when you search hard enough. :-)

So anyone else who runs into this problem, you know the solution.

PostPosted: Sun Apr 20, 2008 2:42 am
by Mattjin
Starting to talk to myself here a little too much. :-)

Does anyone know if the main ECU has any control over the automatic transmission? In particular can the torque converter lockup points be adjusted? The car cruises at steady speed right on the converter lockup TPS value, so even the slightest incline or throttle movement has the converter flaring. It needs to be shifted maybe to lock up maybe another 5% further up the throttle opening. Not only would it make it smoother, but would help economy too.

It appears to lockup at a fixed TPS value, and does not seem to matter what road speed or rpm the car pulls.

What software is used to find the maps? I dont mind doing the work, but how on earth are people finding the maps in amoungst the hex code?

So come on, there must be more people than just me on this forum who own GT-A's!

PostPosted: Tue Apr 22, 2008 8:08 pm
by sub7
I feel your pain... but there are less development for auto tranny this generation of ct9a. Yes, the ecu does control over the auto trans... some development I'd seen is made for airtrek but not published elsewhere...

They use IDA to disassemble the ROM and find all those codes.

Good luck!

PostPosted: Wed Apr 23, 2008 3:25 am
by Mattjin
Any idea where I can get in contact with someone who might know about these sections of the map? What is IDA? A Weber carb :-)

I have never seen an Airtrek other than what people have been talking about on here, but they sound fairly similar in spec.

PostPosted: Fri May 02, 2008 10:30 am
by grayevogta
hello..
how u read ur ecu..what definition file u use...
i try use evo7/evo8..but can oprn the file...
can u share ur definition file with me..
i already download ur file to try open it..but cant open it...
already have install ecuflash...did i miss something here..or just dont have the definition file to read it..

PostPosted: Fri May 02, 2008 12:15 pm
by todd-w

PostPosted: Sat May 03, 2008 4:35 am
by grayevogta
thanks bro..now all the data can been read...

PostPosted: Sat May 03, 2008 4:46 am
by sub7
Mattjin wrote:Any idea where I can get in contact with someone who might know about these sections of the map? What is IDA? A Weber carb :-)

I have never seen an Airtrek other than what people have been talking about on here, but they sound fairly similar in spec.


http://www.hex-rays.com/idapro/
Yes, Airtrek share the same auto-tranny with GTA. Some did flashed GTA ROM in Airtrek without any trouble but I don't see the point of doing it.

PostPosted: Sat May 03, 2008 5:56 am
by grayevogta
Mattjin wrote:It's OK, I figured it out.

All of the data endians were set to "little". Changed them to "big" and everything reads correctly. Amazing what you can do when you search hard enough. :-)

So anyone else who runs into this problem, you know the solution.


where this set sit... i try to find it but dont c where...

PostPosted: Sun May 04, 2008 2:39 am
by Mattjin
Another thing to figure out....

My car will randomly go into anti-lag mode by itself. Mostly happens at higher altitudes than sea level, but has been annoying more than anything. Hit the throttle to overtake and all I get is alot of boost and the ignition retarding to -10 (have a Blitz R-VIT to monitor things). I need to figure out what activates it, and how to set it up better.

The bonus I suppose is that brake-loading up the car at the traffic lights has you leaving the line with full boost, and killing just about any car on the road. :-) Magic stuff!

PostPosted: Sun May 04, 2008 3:52 am
by grayevogta
bro where this setting 'litte' and 'big' place....
try find it but can found it....

PostPosted: Mon May 05, 2008 9:38 pm
by Mattjin
1. Right click on the map that is giving you trouble and select Edit Map

2. Look at the axis that you want. eg for the High Octane Fuel Map you might want to look at the RPM axis. Take note of its name.

3. Select the appropriate Scalings button, and it will bring up a list of all of the different Scalings axis'.

4. Select the one you want, eg. RPM, and select Edit.

5. You will see the Date Endian entry. For mine I needed to change from little to big.

That's it! It should display that exis in the maps correctly.
Hope this helps.

PostPosted: Tue May 06, 2008 6:06 am
by grayevogta
yup it really help..thanks man...
i want start it with speed limit...
but i dont understand...what is on 184 n off 174...what that means

PostPosted: Tue May 06, 2008 9:30 pm
by Mattjin
It means you must do 184 then the motor will cut out, and will turn back on when you slow to 174. This difference is called "hysterisis" and is done to stop the cutout from turning on and off too quickly.

Keep the difference the same, just raise the numbers.