ID725 MS settings
 

Hey guys, I picked up a new set of ID725 injectors. I've done some searching, but haven't found any specific feedback on the MS2 settings people are using.

First the pics of the goods (who doesn't like pics):
https://www.miataturbo.net/attachmen...1&d=1368278159

https://www.miataturbo.net/attachmen...1&d=1368278159

https://www.miataturbo.net/attachmen...1&d=1368278159

This is the page I'm taking my figures from: Injector Dynamics - ID725 Flow Rate and Dead Time Summary

I'm running them in my 2000 NB1, so my fuel pressure is assumed 60psi (stock pump/regulator). Based on that, from extrapolating between the given 12v and 14v figures, I guesstimate the deadtime at 13.2v (what Tunerstudio asks for) is about 0.983.

The "Battery Voltage Correction" seems a little more complicated, but based on the rate of change between the given figures, I came up with the following "chart" (I assumed linearity for simplicity):

So... based on this, the voltage correction looks very linear from 12v to 14v (at 0.110 ms/v), and starts to go down at higer voltages, and go up much faster at lower voltages.

My "Required Fuel" on the 450cc RX8 injectors was 8, I decided to cut it exactly in half to 4 (since the data sheet shows the ID725 flowing 850cc at 60psi).

So, long story short: I'm planning on using 4.0 for my required fuel, 0.983 for my dead times, and 0.110 for my voltage correction (assuming hopefully that the voltages the injectors will see will be in the 11.5-14v range). Do these figures sound comparable to what others are running?

On my 99 NB I have the following settings:

(I have to look up my spreadsheet what fuelpressure I used for my calcs)

deadtime 0,924 (also my values in voltage correction are a tad different so I might have used a different pressure) -btw I am using an MS3.

My reqfuel is at 3.7 but this is on a 1.6l engine...

Thanks Zaphod,

once I got things buttoned up I started driving around/auto-tuning and decided to change my Required Fuel to 4.5
4.0 was a bit too 'large', and wound up over-shooting my previous VE Table by enough to make things uncomfortably lean. Changing it to 4.5, and multiplying every value in my VE Table by 1.3 made things land comfortably rich enough to allow auto-tune to correct things. I prefer to run 10.0-10.5 AFR under boost and lean things up, vs running lean & enrichening.
I also wanted to scale the numbers "up" slightly, as previously on the yellowtops the highest value in my table was 189.