Normal mode skip shift elimination-PCMtec

[Robottrainer]

Not for me....

If anything, mine could stand just a slight firming up in sport/track. By the sounds of things it isn't something I would want to play with until I understand which tables look after that, and roughly which direction to go with it. It's probably something that needs to be looked at in the ALT1 and ALT2 area? Or ALT1/2 looks "out" at those tables.

Having said that, and since I'm using the normal shift characteristics accross the board, which files should I look at to firm up shifts.

I also was looking at something like a Ratio Tek valve body kit which is suppose to firm up and quicken the shifts hydraulically. No one seems to have any experience with these.

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[engineermike]

@Robottrainer as I recall you were having the flare issue in character 1 and switching sport to character 0 fixed it. If character 2 doesn’t flare then you can assigned 2 to sport and track for increased firmness. There’s really no need to look at other calibrations or mechanical “overrides” when 2 is extremely firm and already fully defined in your cal. You just need to use it.

 

[Robottrainer]

@Robottrainer as I recall you were having the flare issue in character 1 and switching sport to character 0 fixed it. If character 2 doesn’t flare then you can assigned 2 to sport and track for increased firmness. There’s really no need to look at other calibrations or mechanical “overrides” when 2 is extremely firm and already fully defined in your cal. You just need to use it.

I guess my train of thought is if 1 was bad and 0 is good, 2 is worse, but it's a good point. Maybe the set up that makes it flair isn't in Alt 2. I'll try it.

 

[Robottrainer]

I guess my train of thought is if 1 was bad and 0 is good, 2 is worse, but it's a good point. Maybe the set up that makes it flair isn't in Alt 2. I'll try it.

So I tried it. Not too bad. 1 to 2nd and 2nd to 3rd is a little bit too long at light throttle and 3rd to 4th a bit short. I set sport and mud odd, ssd Amd LID to Alt 2. The shifts are pretty good. 2nd to 3rd is a bit harsh at times at moderate throttle (feels like a quick double hit). Shifts are quick and sharp. No flares...so far. I'll try it for a few trips and see if I like it. Getting rid of the skip shifts is nice.

 

[Robottrainer]

So I tried it. Not too bad. 1 to 2nd and 2nd to 3rd is a little bit too long at light throttle and 3rd to 4th a bit short. I set sport and mud odd, ssd Amd LID to Alt 2. The shifts are pretty good. 2nd to 3rd is a bit harsh at times at moderate throttle (feels like a quick double hit). Shifts are quick and sharp. No flares...so far. I'll try it for a few trips and see if I like it. Getting rid of the skip shifts is nice.

I found out why. 3 to 4 file rpm is lower than the 2 to 3 file rpm. Most have missed that.

 

[Robottrainer]

I found out why. 3 to 4 file rpm is lower than the 2 to 3 file rpm. Most have missed that.

So does anyone know how Alt 1 and Alt 2 changes the characteristics? Which tables they affect? Are the TCC lock ups different for those two setting. I'm wondering if Alt 2 is a wise characteristic to drive around in, like sport mode. Alt 2 is normally drag which isn't a constant driving mode.

 

[engineermike]

Alt 1 and alt 2 ARE the shift characteristics. Character 1 = alt 1. Maybe I didn’t explain that well enough up front.

The shift and tcc schedules are tied to the drive modes, independent of the characters.

 

[Robottrainer]

OK now I'm seeing it. The TCC schedules, etc are tied to the drive mode modes and not the characteristics so no matter which alt is used the TCC schedule stays tied to the drive mode so drag mode vs track vs sport would be the driving factor. THANKS!

 

[Robottrainer]

OK now I'm seeing it. The TCC schedules, etc are tied to the drive mode modes and not the characteristics so no matter which alt is used the TCC schedule stays tied to the drive mode so drag mode vs track vs sport would be the driving factor. THANKS!

I was concerned that apply a drag characteristic to a normal driving mode like sport or base, it would be causing conditions not good for longevity, even though it seems to work the best in my case

 

[engineermike]

Well, I wouldn’t think ford would allow owners to select it if it wasn’t validated for reliability. The stock calibration even applies full torque during drag wot up shifts. That said, they tamed down the shift torque in the 2024’s.

 

[Robottrainer]

Well, I wouldn’t think ford would allow owners to select it if it wasn’t validated for reliability. The stock calibration even applies full torque during drag wot up shifts. That said, they tamed down the shift torque in the 2024’s.

Guess they woke up!

 

[Robottrainer]

But then again, they are the reason I'm having

Guess they woke up!

Guess they woke up!

But then again, they are the reason I have to bother you and others with this.

 

[cbrtrx]

I populate all the upshifts between load and rpm plus the rpm drop per gear ratio to have the smoothest linear acceleration. Takes time but to me it's worth it. Also make sure to properly calibrate the downshift and coastdown tables as well. I have the car always in the right gear coming out of a turn at any speed, it never has to hunt or clunk it's always ready to smoothly accelerate away.

 

[Robottrainer]

I populate all the upshifts between load and rpm plus the rpm drop per gear ratio to have the smoothest linear acceleration. Takes time but to me it's worth it. Also make sure to properly calibrate the downshift and coastdown tables as well. I have the car always in the right gear coming out of a turn at any speed, it never has to hunt or clunk it's always ready to smoothly accelerate away.

Here's an observation. As some of you know, this all started with an intermittent 3 to 4 and or 4 to 5 flare I was having only on sport or track mode. Playing around with the shift characteristics (alt 1 to normal or 0) cured it.

I tried Alt 2 just for the hell of it. It produces some nice crisp shifts. Very fast. 1 to 2 is a bit harsher but not bad.

Reading other posts it appears alt 2 has a higher torque setting than Alt1 and of course higher than normal or 0. But it also doesn't flare. So what causes the flare? I always thought it was the higher torque in Alt 1 coupled with the higher torque from the super charger. Alt 2 has a higher torque but no flares. So it must be something else in Alt 1 causing it. Ramps maybe?or some other component that creates the shift profile

 

[engineermike]

Gotta be careful generalizing about the shift torques because it varies by gear, input torque and rpm. For instance, for the 4-5, alt 1 has the very lowest shift torque of all at both part and full throttle. Alt 2 has similar shift torque to base/normal except at high torque and rpm, where it doesn't reduce it at all.

@Robottrainer, there is some physical difference causing the flare, like a sticking solenoid or excess clutch clearance. Who knows, but the stock shift characteristics work well with no flare on the vast majority of supercharged cars and trucks. I would call it a "win" because you were able to address your issue with a simple tuning change to account for the physical difference.

That said, I don't claim to have an intimate understanding of the shift logic. I even started a thread to discuss and I don't think many out there really understand the logic and mechanism. Take this FWIW....

I believe some of the parameters are deltas. For instance, there is no inertia phase duration multiplier for base because the multipliers are assumed to be 1.0 for base. Alt2 uses multipliers down to 0.2, as an example.

In the following comparison of base, alt1, and alt2, you can see that base offgoing ramp delta times are largely positive numbers in the higher torque areas. I tend to think this might have something to do with your flare issue.

While I'm no expert on trans tuning, I feel pretty comfortable making changes to the torque modulation tables. If you wanted to test your theory about shift torque and alt1, you could always zero out the alt1 shift torque modulation table and see if that makes it better or worse.

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