TP and WOT

[Toyota John]

I am very interested in this too. This system is so complicated that most professional tuners are not really sure what to do with the DBW tables. I wanted to log and see if the throttle really does start to close myself.

[wparsons]

^^ If you look at the log in my original post you can see the throttle closing as the revs climb. It's pretty consistent in all the logs I've pulled.

If anyone happens to poke around my datazap logs and see one with 100% throttle it's because I edited it for virtual dyno and uploaded the wrong version.

[Toyota John]

I logged my stock frs last night and the throttle position showed 80.4% the whole time. Does anyone know why it's not at 100%?

[steve99]

Originally Posted by jamesm

I don't recall seeing this behavior with the stock roms. It's been a while since I've seen a stock car, though. Next time I have one in for a tune I'll be sure to take note of it.

dug up an old stock log and yep throttle tapers at high rpm

http://datazap.me/u/steve99/brz-g-se...zoom=1737-2172

[steve99]

Originally Posted by Toyota John

I logged my stock frs last night and the throttle position showed 80.4% the whole time. Does anyone know why it's not at 100%?

Ecutek, OFT, Taxtrix all seem to log throttle position differently suspect they might be reading a different RAM address in ECU I would imagine their are several commanded, compensated,actual, throttle sensor ect. Also might be scaling error. All three probably has different guru's trawling the code to extract these addresses and then scale the results. just a stab in the dark though

[s2d4]

Throttle plate opening position is different to the Throttle pedal position for reasons jamesm stated earlier referencing mad_sb's thread.

Toyota John probably hadn't differentiated between the two.

[Toyota John]

I was looking at "Throttle position" using ECUTek. There is also "accelerator angle" which I think is the peddle position. MY car is completely stock other than I am using ECUTek. I wonder if because I am stock with no power adders like an exhaust I am not making enough power for the ECU to pull the power back at the higher RPM range? I am also using the stock DBW tables from B01C. It seem to me from reading about the DBW tables that it is torque based and maybe when it sees the high torque in your cars it is closing the throttle to limit the torque output? List what parts you have added and if you are using the stock DBW table.

[wparsons]

Mostly stock, just a 2.5" perrin catted front pipe and resonated cat-back and OFT. Mine doesn't fall off to 80%, but it definitely tapers off to about 90% consistently. Running the 1.56b Stage 1 OTS map, no tweaks yet.

[Kodename47]

Originally Posted by Toyota John

I was looking at "Throttle position" using ECUTek. There is also "accelerator angle" which I think is the peddle position. MY car is completely stock other than I am using ECUTek. I wonder if because I am stock with no power adders like an exhaust I am not making enough power for the ECU to pull the power back at the higher RPM range? I am also using the stock DBW tables from B01C. It seem to me from reading about the DBW tables that it is torque based and maybe when it sees the high torque in your cars it is closing the throttle to limit the torque output? List what parts you have added and if you are using the stock DBW table.

Have a read of the posts from the top, there's comments from myself and Jamesm regarding the ECUtek output. It's actually nothing to do with the torque you're putting out as the ECU doesn't make that calculation. It's a bit misleading WRT the torque to pedal request tables, but that's just the solution that Subaru have applied. It's just a way of calculating current RPM with pedal position to output a throttle plate angle.

[Luckrider]

Originally Posted by wparsons

Mostly stock, just a 2.5" perrin catted front pipe and resonated cat-back and OFT. Mine doesn't fall off to 80%, but it definitely tapers off to about 90% consistently. Running the 1.56b Stage 1 OTS map, no tweaks yet.

Mine appears to do the same. Here is a look at my most recent log: http://www.datazap.me/u/luckrider/e8...zoom=2863-3245

I did realize that I am not pushing the throttle 100% though. I used to bury it into the floor and I noticed that full throttle is not as WOT as buried in the floor WOT. Here is an old log that goes over 100%

http://www.datazap.me/u/luckrider/hi...oom=9912-10226

[Toyota John]

Originally Posted by jamesm

having the throttle plate close early, at least on an FI car where I've tested it, will cost you power. this is a common mistake made on 86's that goes something like this:

• person sees table labeled 'WOT torque threshold' that seems to read in nm.
• person says 'wow... i want more torque.. awesome!' and bump up the values without adjusting the other dependent tables
• person gets upset when they log their throttle plate angle and see it closing (usually through the midrange because they thought that taking the 'dip' out of that table would eliminate the torque dip)

basically, increasing values in WOT torque threshold causes the throttle plate to open *less*, which is counterintuitive. in order to maintain full throttle angle with a reasonable WOT torque threshold curve you also have to edit the dependent tables.

for a more detailed explanation of how this all works: http://forums.nasioc.com/forums/show....php?t=1537010, though it doesn't apply directly to our ecu, it'll give you an idea of how the tables relate to one another.

To be more application-specific: The 'WOT Torque Threshold' value is divided by the current value in 'Accel Pedal to Desired Torque', which is then used as an input to 'Desired Torque to Throttle Opening' to resolve a desired throttle plate angle.

Do the FRS/BRZ tables work in the same way as the 06+ Subaru?

[Toyota John]

I have been told that 80% throttle opening on ECUTEK is WOT.

[wparsons]

That's not the case with OFT, unless it opens more than 100% at times. Mine peaks at about 98%, but tapers to 90% as the revs climb.

[continuecrushing]

this just confirms my undying hatred for DBW