Transposing fuel maps?

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longracing
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Transposing fuel maps?

Post by longracing »

Just wondering if anyone had say a spreadsheet set-up for transposing a fuel/ignition map or other software for doing this when the rpm/map points are changed? Or is there an easier way?

If not I was thinking of creating a spreadsheet where the current fuel/ignition maps could be entered to generate a new map with averaging to create the new points.

Would anyone find this useful or am I trying to over-engineer the situation? :geek:
Oskar
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Re: Transposing fuel maps?

Post by Oskar »

A feature like that is very useful when tuning engines. You very rarely guess the maps points you need just right from the start.
Ideally this function would be in the tuning interface directly, but one copy-paste away isn't too bad.
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longracing
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Re: Transposing fuel maps?

Post by longracing »

OK. I had a bit of a play and came up with an Excel file to transpose the fuel map but it could also be used for the ignition map if you wanted.

At the moment it only produces one map value but if a couple of people could have a play with it and let me know if it works alright I will move on to making a 10 x 10 or maybe 16 x 16 VE map transposer.

* Instructions - Enter your original map values, rpm points & MAP points in the orange coloured boxes.
- Then enter the new rpm point and MAP point in the green boxes to calculate the new map value in the central green box.

Let me know if there are any problems, if my maths is wrong or if there could be any improvements. ;)
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VE Map - Transposing.xls
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longracing
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Re: Transposing fuel maps?

Post by longracing »

I think there's a problem with my maths in there :oops:
Back to the drawing board...
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longracing
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Re: Transposing fuel maps?

Post by longracing »

This looks a little better and has a few more squares to enter values.
It can even calculate a new value below an original map value using the two values above it. Just enter the new points to try it out.
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VE Map - Transposing.xls
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Fred
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Re: Transposing fuel maps?

Post by Fred »

Good on ya :-)

Hopefully someone pinches your idea and puts it in a tuning tool at some point ;-)

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longracing
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Re: Transposing fuel maps?

Post by longracing »

I'd be glad if someone did pinch it and include it in the tuning software. Hopefully a few people can get some use from it.

Here's my final effort. I've added a few more squares and changed the colours to something that doesn't hurt the eyes so much. It can also be printed off in a landscape format for your records, tweaking on paper or for entering the data in later.
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VE Map - Transposing 9Apr09.xls
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longracing
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Re: Transposing fuel maps?

Post by longracing »

I actually made use of this spreadsheet the other day.
I was trying to upgrade the firmware to MS2_Extra but it kept aborting the download when it tried to set the next page in the uC. So I ended up just upgrading the MS2 firmware.

I used the spread sheet to create a new VE file (all manual inputs), I had changed the RPM & MAP points to better suit the engine. Now the minimum rpm point is 1000 instead of 600 then 1100, since the engine idles at ~900rpm. The changes seem to have gotten rid of the dip in rpm when cracking the butterfly open.

I've attached the spreadsheet if anyone wanted to have a look. Now if I could create a spreadsheet that automatically generates the modified VE file from the original that would be a very useful tool.
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Transposing 12Feb_2010.xls
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