Nissan ECU Tuning

twin-turboz · Joined: 26 Nov 2003 Posts: 62

I was thinking about the scaling and it seems to me that by installing a dual maf and doubling "K" to correct the TP i have overcome my physical airflow limitation. But i am still going to run out of load points on the map and as such have a very non ajustable top end.

Ie. the max load point (58hex for fuel and 60 for timing) will be reached just at the point where i really do want to be able to do the fine tuning.

Am i off my rocker here or does it seem beneficial to expand the load points of the maps so that the max airflow of the engine more closely matches the max load point in the maps.

Has anyone done this?

cb_drift · Joined: 04 May 2004 Posts: 472 Location: New Zealand

YES!!!

very very very benificial to expand the range of the maps to allow a greater tuning range...
lots of ways of doing it - but however its done - its well worth doing from an accurate tuning point of view...

have fun Smile

Kalus · Joined: 23 Nov 2003 Posts: 75 Location: Brisbane, Australia

http://cherrypicker.tripod.com/turboupgradeforvg30dett/id10.html
it has all the details under 'Expanding the Maps'

Cheers
Kyne[/url]

twin-turboz · Joined: 26 Nov 2003 Posts: 62

Thanks for the refrence.

Has anyone actually done this ?

cb_drift · Joined: 04 May 2004 Posts: 472 Location: New Zealand

yes - did this to my old gti-r and expanded the maps to 1.4bar

picked up amazing ammounts of torque by being able to accuratly map the ignition at higher boost levels and you can set the fueling a lot more accuratly as well

as nike say "just do it"

Smile

dzvgtir · Joined: 09 Mar 2005 Posts: 8 Location: Sydney, Australia

I'm trying to expand my maps, and I completely understand the principals. I've read the very helpful ECU Tuning guide at http://cherrypicker.tripod.com/id10.htm

I can understand how to theoretically increase the scales, and the maps. The only thing I'm unsure of is how to actually make those changes in the .bin file. For example, in my SR20DET ROM, the RPM Scale for fuel maps is at 00E0h-00EFh, and holds 16 values that represent the 16-step RPM scale. Now, theoretically, I need to extend this. Let's just say that I want to add 4 more values. I obviously can't just change the next 4 addresses in the ROM file (00F0h-00F3), right? So where exactly do I put the 4 extra values? And how will the ECU know where to look for these new values? The same applies to the maps. If I expand the maps from 16x16 to 20x20 (for example), where do I put all the new values in the ROM file?

Any help would be much appreciated. And if this is a stupid question, or has been answered before, please feel free to politely point me in the right direction Smile

_________________
Jason

midnight · Joined: 17 Feb 2005 Posts: 69 Location: Sydney, Australia

I suggest you read it again.

my understanding is the map will still be 16x16..just the rpm scale will go to a higher rpm.

so you would divide the higher rpm into 16 values...

dzvgtir · Joined: 09 Mar 2005 Posts: 8 Location: Sydney, Australia

hmmm... OK. I thought that was another way of doing it (I know how to do that), but not the ideal way. Because by doing this, we lose resolution (larger jumps between RPM and TP values). In fact, I wouldn't really call this 'expanding' the maps. More like 'compressing' them. Is this really the only way to tune above the current RPM and TP limits?
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Jason

StinkyZ · Joined: 10 Dec 2003 Posts: 111 Location: Tampa, Fl

As far as I am aware adding actual cells to a map is not possible without altering a large amount of the code. The ecu is going to be setup to access certain addresses for the maps and unless you can find those address assignments and alter them there is no way to tell it to use them. I havent heard of anyone actually doing it.

What you are saying is true about changing the resolution. However, I think any minor change in resolution is worth the gain of having control at higher boost. I think there are also ways of putting resolution where you need it. For example you could change the scales so low load areas use only the first 4 columns and high load columns use the remaining 12 columns. This would allow you to have the resolution in the high load columns by having a low resolution in the low load columns where resolution is not so important.

While we are on the subject. Where do you guys think the resolution is most important?

dzvgtir · Joined: 09 Mar 2005 Posts: 8 Location: Sydney, Australia

Yeah, that's what I figured. I guess it was just wishful thinking :)

But I guess you're rigth about using lower resolution down low where we don't necessarily need the same fine tuning capabilities.

Thanks
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Jason

pitstop · Joined: 23 Dec 2004 Posts: 63 Location: USA

Are you using romeditor?

StinkyZ · Joined: 10 Dec 2003 Posts: 111 Location: Tampa, Fl

Unless I'm missing something that is the work of someone that doesnt know what the hell they are doing. You can change the way Romeditor accesses the bin all you want and for that matter you can change the values in the scales and maps all you want, but that still doesnt make the ecu do anything differently. The ecu code determines where the ecu looks for the scales and maps. I'm certain that Romeditor does not have the capability to alter the code in this manner and I doubt anyone here knows how to code it either. Just because you got it to look right in romeditor doesnt mean it works on the ecu.

hpro123 · Joined: 24 Nov 2003 Posts: 50 Location: Athens, GREECE

I concur StinkyZ.

Chris

darkhalf · Posted: Sun Mar 13, 2005 11:48 am Post subject:

interpolation routine would need adjusting. yes you could add extra cells etc to it but would take a little time to achieve and different between types of ecus. would require proper disassembly and then recompilation

rom editor only adjusts tables that are in the ADR file, no code. it is a dumb editor for raw data pretty much

Pingu · Joined: 27 Jul 2007 Posts: 11