No-Lift-Shift, What is it? (Paddle Shift Info Added 9/17/24)

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SeanRitchie

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I think I've received enough calls from the sand community about No-Lift-Shift over the past few years that it deserves a thread here.

No-lift-shift or Flat-Shift is nothing new to the motorsports world. It has been utilized in high performance racing applications since the 70's. Since the off-road world is typically a bit late to the party while the road race guys with 10x the budget of the highest offroad race teams figure things out, it has really only been utilized in off-road race vehicles since the late 2010's.

I will not go into detail about how to properly shift a sequential gearbox in this thread. I want to keep it short and to the point for those interested.

What is "No-Lift-Shift"?

An electronic aid to help dog-engagement (sequential) gearboxes shift using the ECU to cut or "blip" engine power without manually lifting off or blipping the throttle pedal.

How does it work?

A signal is sent to the ECU via strain gauge in shift linkage, shift knob, potentiometer, or position switch on the shift lever. This signal tells the engine management computer to either cut ignition and fuel for an upshift, or "blip" the throttle for a downshift. An engine tuner sets this feature up in the ECU and tunes the system based on those input signals.

The potentiometer (gear position sensor) on the gearbox sends a signal based on shift drum rotation, which triggers the ignition to refire after the shift has completed in the gearbox. This can also be a timed delay through the ECU, but that is a bit crude and can cause damage to the gearbox if there is a slow shift time for some reason like hitting a bump in the middle of a shift.

What kind of "hardware" do you need?

1. An engine management ECU that can accept (2) separate 0-5 volt signals, and allow for a tune to control engine power cut/blip based on those signals.
2. A strain gauge shift knob or strain gauge in shift linkage are the two preferred components based on accuracy of signal to the ECU. You can also use a potentiometer or a position switch, which will work, but not as ideal for a few reasons.
3. A good quality potentiometer (gear position sensor) mounted to the shift drum on a sequential gearbox. Ask your gearbox manufacture if the sensor on your gearbox has the proper "resolution" to send a high quality voltage signal to the ECU.
4. A good engine tuner that understands how dog-engagement gearboxes work, and can tune the ECU based on the signals from the sensors on the shifter and transmission.

What is the advantage of this feature?

Bottom line is that it makes up and down shifting almost effortless. Properly shifting a sequential gearbox in an offroad car is not the easiest thing for many drivers, even those who think they have great coordination. Having the ECU manage the torque loads through the gearbox rather than your foot almost completely alleviates bad or mis-shifts which results in damage to the engagement dogs.


As the sand car community begins to purchase and utilize higher end engine management computers, these features become available. I personally highly recommend this for anyone that is willing to spend the money. When properly tuned, it can greatly help reduce damage to expensive gearboxes due to bad or mis-timed shifts.
 
Sean@Weddle said:
I think I've received enough calls from the sand community about No-Lift-Shift over the past few years that it deserves a thread here.

No-lift-shift or Flat-Shift is nothing new to the motorsports world. It has been utilized in high performance racing applications since the 70's. Since the off-road world is typically a bit late to the party while the road race guys with 10x the budget of the highest offroad race teams figure things out, it has really only been utilized in off-road race vehicles since the late 2010's.

I will not go into detail about how to properly shift a sequential gearbox in this thread. I want to keep it short and to the point for those interested.

What is "No-Lift-Shift"?

An electronic aid to help dog-engagement (sequential) gearboxes shift using the ECU to cut or "blip" engine power without manually lifting off or blipping the throttle pedal.

How does it work?

A signal is sent to the ECU via strain gauge in shift linkage, shift knob, potentiometer, or position switch on the shift lever. This signal tells the engine management computer to either cut ignition and fuel for an upshift, or "blip" the throttle for a downshift. An engine tuner sets this feature up in the ECU and tunes the system based on those input signals.

The potentiometer (gear position sensor) on the gearbox sends a signal based on shift drum rotation, which triggers the ignition to refire after the shift has completed in the gearbox. This can also be a timed delay through the ECU, but that is a bit crude and can cause damage to the gearbox if there is a slow shift time for some reason like hitting a bump in the middle of a shift.

What kind of "hardware" do you need?

1. An engine management ECU that can accept (2) separate 0-5 volt signals, and allow for a tune to control engine power cut/blip based on those signals.
2. A strain gauge shift knob or strain gauge in shift linkage are the two preferred components based on accuracy of signal to the ECU. You can also use a potentiometer or a position switch, which will work, but not as ideal for a few reasons.
3. A good quality potentiometer (gear position sensor) mounted to the shift drum on a sequential gearbox. Ask your gearbox manufacture if the sensor on your gearbox has the proper "resolution" to send a high quality voltage signal to the ECU.
4. A good engine tuner that understands how dog-engagement gearboxes work, and can tune the ECU based on the signals from the sensors on the shifter and transmission.

What is the advantage of this feature?

Bottom line is that it makes up and down shifting almost effortless. Properly shifting a sequential gearbox in an offroad car is not the easiest thing for many drivers, even those who think they have great coordination. Having the ECU manage the torque loads through the gearbox rather than your foot almost completely alleviates bad or mis-shifts which results in damage to the engagement dogs.


As the sand car community begins to purchase and utilize higher end engine management computers, these features become available. I personally highly recommend this for anyone that is willing to spend the money. When properly tuned, it can greatly help reduce damage to expensive gearboxes due to bad or mis-timed shifts.
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This is basically how the BMW and VW SMG tranny's work.

Yes?
 
If you are referring to the new DCT (Dual Clutch Transmission), yes and no. Those are half sequential and half automatic. But they still utilize ECU management to shift them. The new trans in the Can-Am works the same way as these.

Our gearboxes/transaxles are actually quite antiquated in design, which works well for simple, rugged, reliability. The No-Lift-Shift feature for them is actually pretty simple in terms of how they are tuned compared to the new DCT designs.
 
Bruh, that technology is from the 80s! My 1987 Bayliner had that! 😆

Sorry, that's as close as I can relate LOL

Great topic Sean! Keep em' coming!
 
Sean@Weddle said:
If you are referring to the new DCT (Dual Clutch Transmission), yes and no. Those are half sequential and half automatic. But they still utilize ECU management to shift them. The new trans in the Can-Am works the same way as these.

Our gearboxes/transaxles are actually quite antiquated in design, which works well for simple, rugged, reliability. The No-Lift-Shift feature for them is actually pretty simple in terms of how they are tuned compared to the new DCT designs.
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Thank you. 👍🏼

How does the tranny in the Talon work then?
 
How well ,or not,does this work with a torque converter/sequential car?
 
fabr said:
How well ,or not,does this work with a torque converter/sequential car?
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Great question.

The torque converter adds a bit of complexity due to the inertia effect of the converter and how the input shaft is still under torque load even after you cut the power. But, this is what we use in the big class 1 desert race cars, and it does work well in most instances.

Shifting can still be a bit sluggish when the car is under a heavy load, usually when accelerating through a sand wash or soft sandy terrain. Due to the excess drag from the soft terrain, and extra driving force of the torque converter, there can still be times where even with No-Lift-Shift active, you may not be able to physically shift the car if the dogs have not unloaded.

The strain gauge is the best in these scenarios as it will trigger the ignition cut based on how hard you pull on the shifter, but there still may be a slight delay in the time it takes the dogs to unload and allow the shift mechanism to turn over and shift into the next gear. There is not much you can do here other than manually let off the throttle just a bit and time the shift once the car torque has unloaded.

Clutch cars are less susceptible to this since the engine has a more solid connection to the gearbox, so when you cut the power to the engine, the trans input shaft speed changes instantly with the engine crank speed. Whereas a torque converter will want to keep driving that input shaft, even after the engine power has been cut.
 
I have a converter car and have wishy-washied back and forth on implementing this for a few years. I just cannot see it working well especially down shifting. I have a Fortin frs5,are you confident it would/could be reliable ?
 
I'm placing an order for a new Albins from Weddle (via Funco) in the next day or so for my Funco build. Can this be added to an Albins? Car will have a Holley Pro system. Any idea if that supports the no lift shift parameters required?
 
fabr said:
I have a converter car and have wishy-washied back and forth on implementing this for a few years. I just cannot see it working well especially down shifting. I have a Fortin frs5,are you confident it would/could be reliable ?
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It's less about the gearbox and more about the tuner that sets the parameters. There are a few Fortins in class 1 cars with converters that utilize No-Lift-Shift. I do not have any direct experience with them though.
 
Dockmaster said:
I'm placing an order for a new Albins from Weddle (via Funco) in the next day or so for my Funco build. Can this be added to an Albins? Car will have a Holley Pro system. Any idea if that supports the no lift shift parameters required?
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As stated above, it's more about the ECU and the tuner that makes this system function properly. But yes, the Albins sequential will allow for this system.

I have heard that the newer Holley systems can accept some of these inputs, but I know the older ECU's do not. You would need to know what ECU you are going to have and ask Holley if it can accept the signal from the shifter and the trans sensor, as well as be tuned.
 
Sean@Weddle said:
It's less about the gearbox and more about the tuner that sets the parameters. There are a few Fortins in class 1 cars with converters that utilize No-Lift-Shift. I do not have any direct experience with them though.
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The geartronics flatshift system is a bit different in that it does not rely on the engine ecm necessarily and can work with old school no ecm cars as well as modern ecu's. It uses ,usually ,a load cell in the shift linkage/cable or a load cell shifter handle to initiate the power cut and a sensor on the shift barrel to verify the shift is completed before power is resumed. The power cut time is always different depending on how long the shift takes to complete.

The geartronic system will not work well at blipping the throttle for downshifts however. It CAN trigger a blip either pnuematic or solenoid but unless on something like a hayabusa or other small fast revving engine not recommended. In my case of the torque converter that can ,at times, be a problem downshifting unless I let off and then blip the throttle I wouldn't be able to have the downshift function. There is a bunch of info on their site explaining the how and why.

I haven't any knowledge of whether any of the more sophisticated systems use shift barrel feedback to verify shift completion.

For my purposes it seems like the ideal system. It is used pretty extensively across the pond and has been around for a long time. Pretty inexpensive as well.

Geartronics claim that the closed loop system will lessen wear and tear on the dogs since power would never be resumed before full shift completion which could occur on time based ,open loop systems such as ,i think, most are. Someone please correct me if I have that wrong.
 
fabr said:
The geartronics flatshift system is a bit different in that it does not rely on the engine ecm necessarily and can work with old school no ecm cars as well as modern ecu's. It uses ,usually ,a load cell in the shift linkage/cable or a load cell shifter handle to initiate the power cut and a sensor on the shift barrel to verify the shift is completed before power is resumed. The power cut time is always different depending on how long the shift takes to complete.

The geartronic system will not work well at blipping the throttle for downshifts however. It CAN trigger a blip either pnuematic or solenoid but unless on something like a hayabusa or other small fast revving engine not recommended. In my case of the torque converter that can ,at times, be a problem downshifting unless I let off and then blip the throttle I wouldn't be able to have the downshift function. There is a bunch of info on their site explaining the how and why.

I haven't any knowledge of whether any of the more sophisticated systems use shift barrel feedback to verify shift completion.

For my purposes it seems like the ideal system. It is used pretty extensively across the pond and has been around for a long time. Pretty inexpensive as well.

Geartronics claim that the closed loop system will lessen wear and tear on the dogs since power would never be resumed before full shift completion which could occur on time based ,open loop systems such as ,i think, most are. Someone please correct me if I have that wrong.
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The geartronics system is doing the same thing through their standalone system that you would through a high end motorsports ECU and having a tuner set up the system.

The question becomes how is the Geartronics standalone system telling what ever ECU you have to cut or blip power? That's a question for your engine tuner, I don't have that answer.

One thing I forgot to mention is having a drive-by-wire throttle body to blip for downshifts. If you have a cable actuated throttle body, there is no good/easy way to actuate a blip for downshifting.

One of the major worries I have with a closed loop system is that if it has been tuned specifically for road racing applications, we have often seen issues with those type of "tunes" tearing up gearboxes in offroad cars. They don't take into account the spinning and inertia of the wheels after the ignition has been cut since road cars would never shift when the tires have broken traction. I would ask if you could tune this closed loop system independently for each application.

I was recently on the phone with some high end road race (Indy Car and IMSA) engineers after one of the ST6 trophy truck gearboxes was destroyed after they installed paddle shifters. They had tuned the system to work the same as their road race cars, and the shift times were so short and precise that the dogs got torn off almost all of the gears. Once I explained wheel spin and inertia from the weight of the heavy tires, they were able to "dumb down" the shifting tune and everything is working properly.

So, I would recommend a shift system that has been tuned by an offroad specific tuning shop that knows and understands the factors involved with this type of use.
 
Sean@Weddle said:
The geartronics system is doing the same thing through their standalone system that you would through a high end motorsports ECU and having a tuner set up the system.Pretty much for the most part.

The question becomes how is the Geartronics standalone system telling what ever ECU you have to cut or blip power? That's a question for your engine tuner, I don't have that answer.It can operate independent from the engine ecu . It uses a load cell either in the linkage or from a load cell shifter handle.Remember I am discussing their "manual" flat shift unit not their paddle shift system. The manual system is not recommended for downshifts . Downshifting would be done as always. I like that with a converter and not a drive by wire.

One thing I forgot to mention is having a drive-by-wire throttle body to blip for downshifts. If you have a cable actuated throttle body, there is no good/easy way to actuate a blip for downshifting. I believe that is a requirement for their paddle shift system.

One of the major worries I have with a closed loop system is that if it has been tuned specifically for road racing applications, we have often seen issues with those type of "tunes" tearing up gearboxes in offroad cars. They don't take into account the spinning and inertia of the wheels after the ignition has been cut since road cars would never shift when the tires have broken traction. I would ask if you could tune this closed loop system independently for each application. Yes it is capable of that.There is a short vid on their site showing a car racing in the mud with lots of wheel spin.

I was recently on the phone with some high end road race (Indy Car and IMSA) engineers after one of the ST6 trophy truck gearboxes was destroyed after they installed paddle shifters. They had tuned the system to work the same as their road race cars, and the shift times were so short and precise that the dogs got torn off almost all of the gears. Once I explained wheel spin and inertia from the weight of the heavy tires, they were able to "dumb down" the shifting tune and everything is working properly.I can see that.

So, I would recommend a shift system that has been tuned by an offroad specific tuning shop that knows and understands the factors involved with this type of use.As a failsafe feature power is never reapplied until the barrel/drum sensor verifies the shift is completed. I am going to delve into this deeper with them next week. I've had my eye on this for a few years now.
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Here is a vid using their paddle shift system with a BMW v10 4wd in the mud. It's a paddle and not the no lift only system like I am talking about. I don't have a fancy engine management setup..
 
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Unless it monitors shift drum rotation to verify shift is completed before resuming power I would not be interested. It appears to be a time based only unit .
 
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