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Proper Gear Shift Setup.


K4Tuning

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Hey all Link G4X PnP user here for my USDM evo 9. Questions regarding setting up the gear shift control in my car. My car is standard 5spd trans with synchros. On the newest firmware, Do I need to set up all of the "Dog Unload" stuff as well as the Main Shift stuff or will I just use the Main Shift settings being that I have a standard synchro transmission? And if I do need to set up the dog unload settings, how different are they going to be from my main shift settings? Or will they be similar? Trying to get the best shift I can. Thanks for any info.

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The idea of a seperate dog unload and main shift stage is with dog engagement gears you want an short/sharp torque reversal just to get the dogs separated, once they have released the goal is just to slow the engine down enough so the shaft speeds arent vastly different for engagement.  

In a synchro gearbox there is no undercut on the dogs and the clutch does the unloading so in theory you dont need a different cut for the disengagement Vs engagement.  I would set the dog unload duration to 0, so you dont need to worry about any of the dog unload settings, your whole shift will be handled by the "main shift" settings. 

For a synchro flat shift, the start shift mode would usually be "digital input" using a clutch switch, the end mode can be digital input or time.  Digital input means the cut will be active for the whole time the clutch is pressed, time means you would have a table controlling how long the cut is applied for for each gear.  Both have pros and cons - to get the shortest possible shift in digital end mode the clutch switch needs to trigger in the right points (adjustable) and that will change with clutch wear etc.  For the time based end mode the driver needs to be fairly consistent with how fast he pulls the lever and the timing between pedal and lever movement. 

Start with about 80% severity and 200ms duration if using time mode.    

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@Adamw Thanks, That answered that portion of my question. I have a couple other questions as far as the ignition trim and torque reintroduction time. With the ignition trim, is this supposed to be a small amount of retard just to lower the engine tq? Or is this supposed to be aggressive, almost like an antilag ignition retard to help aid in keeping the turbo up to speed? When doing a WOT pull in my car ignition timing is around 5* right now. I have my main shift cut at 80% and my ignition trim is at -30* and torque reintroduction time is at 40ms. Does this sound appropriate? Or should I make a change to the ignition trim and reintroduction time? Thanks again for the help.

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