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Number of grids in calibration table


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Happy New Year.

I am trying to run MX5 NB2 with air flow meter.

I have the data from 0-5V in the calibration table, but I would like to enter "24" data compared to the default grid of "16".

I tried thinning out the "24" data to "16" but could not start the engine.

Is it possible to increase the grid to "24" or more?

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No, the max for a cal table is 16.  16 Vs 24 is not going to prevent the engine from running, so you have some other issue.  Note the axis breakpoints are free so that means you can close up the increments at the zero end of the calibration where the resolution is needed then open up the breakpoints at higher air flows where the "curve" is closer to a straight line. 

Personally I would say to not even bother with a MAF, your life will be a whole lot easier if you stick with speed density.  There is not proper MAF support in Link ecu's, you can make them work but it will be a lot more work with fuel control that is not as good as SD.  

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AdamW is completely spot on.

I've got two Eunos Roadsters - the JDM MX5, both on G4X) - most of the MX5s modders I know try and ditch the AFM/MAF as soon as possible since it's a power restriction and frankly a pain to tune for. You want either Alpha N (TPS primary fuel load, secondary BAP, IAT) or Speed Density (SD) (which means MAP and IAT) for your fueling, depending on what your mods are... most will want the Speed Density setup if their map signal is good.

Assuming you probably have the original intake manifold, your map signal should be perfect - what you want is to hook up the MAP signal with a vacuum line and setup acceleration enrichment (AE) based on the TPS signal, which on your NB will be a nice variable one. Load on MAP. AE to give it the smash-the-pedal drivability - AE removes the BOG that you get when you suddenly open the throttle plates.

My setups, if you want a reference.. well they're two extremes... but none of them involve MAF/AFM setup.

My ITB car has a terrible MAP signal (RS Aizawa Intake Manifold - 4AGE ITBS - it's a spikey signal at low load) so I run Alpha N there. I still use MAP for fuel pressure reference stuff but the secondary load source is BAP.

My turbo car retains stock intake manifold so runs MAP, vacuum from a port just behind the throttle body.

You can see an example of my maps for the turbo car here  https://trull.org/alex/src/ecu_maps/G4X/Blue/ it isn't a map for your car but it is an example of a car running with a MAP signal and no AFM/MAF. The higher number map file is the 'more tuned' :D 

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In the instructions for the NB2 plugin, the following jumper is described and I wanted to see if I could get it to work with the stock MAF.

"When using the stock MAF with An Volt 3, the jumper must be placed so that the two pins are connected."

I understand that there are many limitations that come with using MAFs.

Thanks for the advice!

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Yes you can use it for logging mass air flow, it can be helpful for tuning functions such as VVT and comparing to estimated mass air flow from the modelled fuel equation to confirm your data is all correct.  But it is typically not used as part of the strategy to run the engine.  

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