Importing ignition map

[se7ensport]

Couple of ignition map questions:

1.I've got an ignition map for my engine from another ECU which will give me a headstart in getting the VEMS map correct, I've been able to export a .txt file, its not 12x12, is there a simple way to convert the figures and import?


2. Can I generate a table based on known ignition min and max advance i.e. my set up should be 17BTDC@1200, 36BTDC at 3500 (max advance), max engine revs 7150?


Cheers

Alex

[rob@vems.co.uk]

What resolution is the map?  The simplest method would be to use a spreadsheet to interpolate the values, but, The best bet would be to analyse the table and find the points where the gradients change and use this to define a new table...

You have noticed that you can set the kpa(TPS in your case) and RPM points to your own values, this is because certain areas in the engine's operation, need more detail than others - for example around idle and part throttle, where as higher engine speeds need less detail.
With VEMS you identify the significant points of change in the map and let it interpolate the straight lines.

[se7ensport]

The maps I have are 10x10

and look like this:

Map 1
mapBins=0,36,51,65,80,94,108,123,137,152
rpmBins=5,13,22,30,38,47,55,64,72,80
advance9=14,24,24,24,27,28,29,31,32,34
advance8=14,25,24,25,27,29,30,31,32,34
advance7=14,26,24,25,27,29,30,30,32,35
advance6=14,26,25,26,28,31,33,31,33,36
advance5=14,27,25,28,28,33,35,35,35,37
advance4=14,28,26,28,29,34,37,37,37,39
advance3=14,29,26,28,30,35,38,38,38,40
advance2=14,29,28,29,34,37,39,39,40,40
advance1=14,30,32,32,38,41,43,43,43,44
advance0=14,26,28,29,31,34,35,35,35,35

Map 2
mapBins=0,36,51,65,80,94,108,123,137,152
rpmBins=5,9,18,27,35,44,53,62,71,80
advance9=10,11,22,24,27,29,29,31,32,34
advance8=10,11,22,25,27,29,30,31,32,34
advance7=10,11,22,25,27,29,31,32,33,35
advance6=10,12,23,26,28,31,33,33,33,36
advance5=10,12,23,27,28,33,35,35,36,37
advance4=10,13,25,27,29,34,37,37,37,39
advance3=10,13,25,28,30,35,38,38,38,40
advance2=10,14,28,28,34,37,39,39,39,40
advance1=10,14,32,32,38,41,43,43,43,43
advance0=10,17,21,25,31,35,37,37,37,37

[cliffb75]

What resolution is the map?  The simplest method would be to use a spreadsheet to interpolate the values, but, The best bet would be to analyse the table and find the points where the gradients change and use this to define a new table...

You have noticed that you can set the kpa(TPS in your case) and RPM points to your own values, this is because certain areas in the engine's operation, need more detail than others - for example around idle and part throttle, where as higher engine speeds need less detail.
With VEMS you identify the significant points of change in the map and let it interpolate the straight lines.

What he said 

I usually import the existing map into excel then create a big map with both the existing breakpoints and the new breakpoints on the axes. Interpolate / extrapolate the information, and then create an output map with the new breakpoints, that I can export to the ECU. Make sure you actually look at the shape of the map so that you keep those charcteristics in the new map (as Rob mentioned).

[rob@vems.co.uk]

The maps I have are 10x10

and look like this:

Map 1
mapBins=0,36,51,65,80,94,108,123,137,152
rpmBins=5,13,22,30,38,47,55,64,72,80
advance9=14,24,24,24,27,28,29,31,32,34
advance8=14,25,24,25,27,29,30,31,32,34
advance7=14,26,24,25,27,29,30,30,32,35
advance6=14,26,25,26,28,31,33,31,33,36
advance5=14,27,25,28,28,33,35,35,35,37
advance4=14,28,26,28,29,34,37,37,37,39
advance3=14,29,26,28,30,35,38,38,38,40
advance2=14,29,28,29,34,37,39,39,40,40
advance1=14,30,32,32,38,41,43,43,43,44
advance0=14,26,28,29,31,34,35,35,35,35

Map 2
mapBins=0,36,51,65,80,94,108,123,137,152
rpmBins=5,9,18,27,35,44,53,62,71,80
advance9=10,11,22,24,27,29,29,31,32,34
advance8=10,11,22,25,27,29,30,31,32,34
advance7=10,11,22,25,27,29,31,32,33,35
advance6=10,12,23,26,28,31,33,33,33,36
advance5=10,12,23,27,28,33,35,35,36,37
advance4=10,13,25,27,29,34,37,37,37,39
advance3=10,13,25,28,30,35,38,38,38,40
advance2=10,14,28,28,34,37,39,39,39,40
advance1=10,14,32,32,38,41,43,43,43,43
advance0=10,17,21,25,31,35,37,37,37,37

Nice... You could just chuck those numbers in to the 12x12 map and not bother with the final two rows and columns.
Just to get started

[se7ensport]

I'll copy and paste work them in and see how I get on.... just need to set the trigger correctly and I should get it running tonight....

[rob@vems.co.uk]

Cool stuff,
To be honest I'd look at extending the MAP bins, the suggested bin placings are:
0,2,5,12,23,35,53,75,115,165,225,255

Which you should be able to map some of your existing values onto.

You might also get some benefit from adding a break point 200rpm either side of your intended idle speed, this can help clean up the idling.

so your RPM steps would be: 700, 900, 1100, 1300, 2200, 3000, 3800, 4700, 5500, 6400, 7200, 8000