Zen's Cable Throttle tune

[zenvirzan]

Hi all

Overview
I've been doing some experimentation with the "Desired Torque" table and I've managed to entirely remove it from the DBW calculations. This means the logic behind the intake butterfly valve is now:

• Physical Accelerator Pedal position -> Throttle Duty Cycle table (sets the throttle curve) -> Relative Throttle Plate position table (sets the 1-to-1 output, plus a little extra at closed throttle for idle)

That's it! Now we're similar to a cable throttle (but with DBW idle, of course)! No more weird adjustments in the background, you have direct control over your Throttle butterfly valve!
Traction control and cruise control work exactly as per stock, too!
I feel like this is a game changer for those using FI too, making the stock ECU far more predictable, which was the main driving force behind this tune

Warning

• I'd suggest only those comfortable with modifying their tune mess with this file, as it does make some extremely large changes.
• Please make sure that during the conversion process when opening the tune (if your firmware is not the same as mine posted, usually Versatuner warns you about this when opening the tune) that none of the tables have been messed up.
• This also likely results in a slight power loss as the throttle will now actually be fully open on demand, which may slow the air velocity. I don't care though, it's much nicer to drive now

How to use
This tune is designed to be a starting point, built directly on top of the stock tune. While there is nothing stopping you from flashing this tune directly, I'd highly recommend building a new tune on top of this one, or copying your favourite tune's relevant tables across. I personally don't use this throttle duty cycle, I have mine hit 84 at only 70% throttle as I find I never bottom out the pedal when I'm expecting full power, but everyone is different.
Likewise, this tune does not have any fan temp adjustments, fueling changes, oiling changes, or anything else that I'd suggest taking a look at.

Modified tables

• Calculated Engine Torque: now represents butterfly position rather than "torque". This has been reverse calculated to match the OEM table. It looks messy, blame Mazda
  
• Desired Engine Torque: now represents butterfly position, and thus the butterfly position should match the X axis (throttle position)
  
• Relative Throttle Plate Position: "calculated torque" now represents "requested butterfly position". This table should match the X axis and top out at 84. I swapped my "90" column with "84" to ensure it lines up perfectly. If you see any values that don't align properly, make sure to fix them.
  
• Throttle Duty Cycle (A-D): now represents only the gradient you're looking for. Note that cable throttles usually have a slight cam where the cable connects to allow more precise movements at low throttle levels. I've implemented something similar here.
  

I also updated the max operating load to make sure it didn't close the throttle early for any reason. This isn't strictly required.

For those curious
I reverse calculated the OEM "Desired Torque" table with respect to the OEM throttle plate position table while I was doing the "Calculated Engine Load" reverse calculations, and the results are quite interesting. Note that this is NOT including the throttle duty cycle, which will slightly skew the results. The X axis is the throttle position post-throttle duty calculation, not the direct accelerator pedal position.

You can see that we're never really ever at full throttle on the stock map. Some tunes that increase the desired torque allow the throttle to be fully open in some areas, but a lot of the throttle plate scaling is so extreme that they never really hit WOT. Just really interesting to look at IMO.

Disclaimer
I'm just a random dude on the internet--this tune is provided with no expected support or warranty. By flashing my tune, you agree that I am not liable for any damages caused.

[wcs]

Wow, this is terrific!

If it wasn't pissing down rain and only 7c outside I would take this for a spin.

I will update a tune with your suggestions and report back when I can get an opportunity.

[Walle]

finally got some time to read in on this.
very interesting aproach.

did you got any problem on low load running and car "jumping" ?

im going to try this together with the Bridgeport and huge exhaust port I'm just finishing thought winter is coming and don't have garage to.....

[zenvirzan]

did you got any problem on low load running and car "jumping" ?

Not entirely sure what you mean by jumping, unless you mean first gear bucking which I haven't noticed any difference. If there are issues in that regard, they should be solvable my making low-throttle even less sensitive in the throttle duty map. Certainly no influence on cruising nor WOT as far as I can tell

I should probably say that I haven't tested this against a bridgeport's idle process which pushes the OEM logic to the extreme. I'm not sure exactly what method the ecu uses to manipulate the throttle at idle: whether it manipulates the "desired torque", the "relative throttle position", or entirely after the fact (it might manipulate the throttle valve directly after/irrespective the rest of the calculations, which would make sense so it can hold idle without needing any of those maps to have any specific values)

Not something I really care to test until my bridgeport is ready to go

[Walle]

bunny hopping / stuttering / jerking in 1st and 2nd on very low load probably in area where Idle ecu logic is taking over.

[zenvirzan]

I do experience that a little when it's cold with high idle, I don't believe we can control the conditions it uses to determine whether to use idle logic or driving logic. It'd be nice to be able to configure the idle vacuum requirements but not possible from the looks of things

[dcox11b]

Just to clarify. You are saying that the values in the tables you posted should be copied exactly as the ones in your picture correct? And not to use the converted values that happen when versatuner changes values based on calibration.

[zenvirzan]

That's right, they're there for reference, as the provided tune will get manipulated by Versatuner if your calibration is different

[dcox11b]

Thanks for clearing that up, years down the road people will read this and we might not be around to answer. I think it might help to make a notepad text file with the table values so they don't get lost if the pics break one day.

[zenvirzan]

First post updated with a bunch of different file formats