The throttle tables mentioned above in
post 12 have been discovered and defined in the XDF’s with the help of
vtl, thanks again chief
, you’ve always given to this platform without any personal gain or reward.
Now IJE0S (MSD81) and I8A0S (MSD80) can also enjoy a more responsive throttle without the need to migrate to the IKM0S bin from the 1M as I did on my car, although I’ll probably continue running the IKM0S bin on my car. The 1M was the most powerful production N54, it certainly a move in the right direction to use the IKM0S as a base for my custom tune.
vtl will do a public announcement and release the XDF’s after all testing has been conducted. Currently
vtl,
titium,
Socket,
DR-JEKL and
RJ019 are running the throttle fix on their cars. Between these 5 cars, we have a top mount single turbo, a low mount single turbo, aftermarket twins, and stock twins, and we got MSD80 and MSD81 with IJE0S and I8A0S bins. All working well so far
, and everyone is enjoying the new discovery. No one had to migrate to IKM0S like I did, and their throttle feels just as great as it feels on my car (and same as the 1M too).
Without going into too much technical details, the tables that have been discovered act as a filter to the driver accelerator input.
These tables govern how the accelerator will respond in the following situations:
1- If the car stationary
2- If the car is moving at high/low speeds
3- If the car is reversing
4- Whether the clutch pedal is pressed in or not
5- Sport Mode on DCT and Auto (still have a slower throttle plate actuation compared to the 1M tables)
For example, if reverse is engaged, the throttle response will be very numbed down. This makes sense of course, because it’s assumed that when reversing you need to exercise care, and look around… etc. There's no need for a more responsive throttle, or a throttle plate that opens quicker once the accelerator is pressed.
Interestingly, the 1M throttle filtering tables are all ZEROED out! i.e. there’s absolutely no throttle corrections or filtering regardless of the situation that the car is in, doesn't matter if it's reversing, doing 250km/h or crawling at 10km/h in a car lot, there's no throttle correction by the DME
This makes the throttle feels super responsive, the accelerator also feels very consistent, as it always behaves in the same manner regardless of the situation, and it actuates the throttle plate very quickly to open/close (read
post 12 above on a more thorough review after I migrated to IKM0S on my car).
Lastly, this throttle response fix is not the same as switching linear throttle on/off, people don't get it! Linear throttle option in MHD has to do with torque request table in the tune bin. I.e. if you press 10% throttle, the DME will target 10% of the available torque at the current rpm. Linear throttle means a 1:1 relationship, so 20% accelerator travel = 20% of the available torque, 40% accelerator = 40% torque... etc. The reason MHD included the linear throttle tick box is because from factory these cars have a non-linear throttle, for example: 10% throttle is 20% torque, 40% throttle is 80% torque... etc. by the time you get to 60% accelerator travel, the engine is already producing 100% of its torque, so it's basically full throttle at only 60% accelerator pedal travel, and the remaining 40% of the pedal travel is just a deadzone that doesn't do anything. In my opinion, ticking that MHD linear throttle option is a must, specially when these engines are tuned, the torque is very hard to control, and the longer pedal travel really helps applying the torque smoothly on corner exit without spinning the wheels.
The throttle fix that has been recently discovered is completely different to the throttle mapping and torque request tables, I thought I should clarify that because it's very easy to mix between a sharp throttle response, and a stupid bloated over-reactive accelerator input where 30% accelerator travel is equal to 60% of the available engine torque.