722.6 swaps.
722.6 swaps.
How about that k3 port drilling to 4mm, I need to do oil change anyway so is it worth to get it done also?
As I understand 722.6 have only 3-4 shift synchronized and that's why only that shift is causing problems. Till now it was unclear for me, I thought 722.6 have all shifts non-synchronized.
How about that k3 port drilling to 4mm, I need to do oil change anyway so is it worth to get it done also?
(02-06-2015, 05:07 PM)raysorenson When an auto trans shift occurs that requires one friction component (clutch or band, but not one way clutch) to release at the same time that another friction component is applied (clutch or band, but not one-way clutch), the shift is called "synchronized". If the friction component that must release for the synchronized shift to occur releases too early, there is a shift flare. If the friction component that must release for the synchronized shift to occur releases too late, the gears (planetary gears) are mechanically locked to the transmission case. This second scenario is often catastrophic, the first is annoying. Applying 2 friction components that result in locking the gearset to the case is how a trans brake works.
An example of a synchronized shift is the 1-2 in the old 3 speed Ford FMX trans. It has a ravigneux planetary gearset. The forward clutch is applied in forward gears, the low clutch is applied in first, the intermediate band is applied in 2nd. The low clutch must release when the intermediate band is applied for the 1-2 shift to occur. Later, Ford made another transmission based on the FMX that exploited the ravigneaux planetary gears' capability of 4 forward gears. This was the AOD, which became the AOD-E and later the 4R70W. They got around the typical synchronized 1-2 shift inherent of the ravigneaux planetary by installing an intermediate clutch splined to a huge, beefy intermediate one-way clutch, which is essentially a very nice ratchet. With the intermediate one-way clutch, when the intermediate friction clutch applied for the 1-2 shift the low clutch could take it's sweet time disengaging, it's release timing no longer mattered for the 1-2 shift. This is a "non-synchronized" shift. It cost Ford money to engineer and produce these extra parts, and that's why auto transmissions have synchronized shifts.
The modern ZF 6HP26 6 speed trans found in almost every vehicle worth mentioning for a while is a fully "non-synchronized" trans. I suspect that most shifts in all the latest transmissions are non-synchronized wherever possible. It's a bummer that the synchronized 3-4 shift hadn't been eliminated by the time the .6 came out.
Actually most newer stuff is not. Physical size is an issue with doing this. And remember that the 722.6 was released in the U.S. in 1996. Earlier in other countries and had probably been on the table for several years before that. Also it simply is not an issue in factory cars with the computers to deal with it. I run a shift cut feature on my gas car with a standalone and I cut the timing for .2sec. Shift is over and back to full power. Dual clutch transmissions also target the next gears rpm during the clutch disengagement. Very common strategies.
(02-06-2015, 05:30 PM)erx As I understand 722.6 have only 3-4 shift synchronized and that's why only that shift is causing problems. Till now it was unclear for me, I thought 722.6 have all shifts non-synchronized.
How about that k3 port drilling to 4mm, I need to do oil change anyway so is it worth to get it done also?
The opening of the k3 port does help a lot. It allows filling the k3 clutch at lower pressures faster. This prevents the pressure spike in the valve body that will prematurely release the b2 clutch making the flare worse.
whipplem104
02-06-2015, 05:38 PM #52(02-06-2015, 05:07 PM)raysorenson When an auto trans shift occurs that requires one friction component (clutch or band, but not one way clutch) to release at the same time that another friction component is applied (clutch or band, but not one-way clutch), the shift is called "synchronized". If the friction component that must release for the synchronized shift to occur releases too early, there is a shift flare. If the friction component that must release for the synchronized shift to occur releases too late, the gears (planetary gears) are mechanically locked to the transmission case. This second scenario is often catastrophic, the first is annoying. Applying 2 friction components that result in locking the gearset to the case is how a trans brake works.
An example of a synchronized shift is the 1-2 in the old 3 speed Ford FMX trans. It has a ravigneux planetary gearset. The forward clutch is applied in forward gears, the low clutch is applied in first, the intermediate band is applied in 2nd. The low clutch must release when the intermediate band is applied for the 1-2 shift to occur. Later, Ford made another transmission based on the FMX that exploited the ravigneaux planetary gears' capability of 4 forward gears. This was the AOD, which became the AOD-E and later the 4R70W. They got around the typical synchronized 1-2 shift inherent of the ravigneaux planetary by installing an intermediate clutch splined to a huge, beefy intermediate one-way clutch, which is essentially a very nice ratchet. With the intermediate one-way clutch, when the intermediate friction clutch applied for the 1-2 shift the low clutch could take it's sweet time disengaging, it's release timing no longer mattered for the 1-2 shift. This is a "non-synchronized" shift. It cost Ford money to engineer and produce these extra parts, and that's why auto transmissions have synchronized shifts.
The modern ZF 6HP26 6 speed trans found in almost every vehicle worth mentioning for a while is a fully "non-synchronized" trans. I suspect that most shifts in all the latest transmissions are non-synchronized wherever possible. It's a bummer that the synchronized 3-4 shift hadn't been eliminated by the time the .6 came out.
Actually most newer stuff is not. Physical size is an issue with doing this. And remember that the 722.6 was released in the U.S. in 1996. Earlier in other countries and had probably been on the table for several years before that. Also it simply is not an issue in factory cars with the computers to deal with it. I run a shift cut feature on my gas car with a standalone and I cut the timing for .2sec. Shift is over and back to full power. Dual clutch transmissions also target the next gears rpm during the clutch disengagement. Very common strategies.
(02-06-2015, 05:30 PM)erx As I understand 722.6 have only 3-4 shift synchronized and that's why only that shift is causing problems. Till now it was unclear for me, I thought 722.6 have all shifts non-synchronized.
How about that k3 port drilling to 4mm, I need to do oil change anyway so is it worth to get it done also?
The opening of the k3 port does help a lot. It allows filling the k3 clutch at lower pressures faster. This prevents the pressure spike in the valve body that will prematurely release the b2 clutch making the flare worse.
(02-06-2015, 05:38 PM)whipplem104 Actually most newer stuff is not. Physical size is an issue with doing this. And remember that the 722.6 was released in the U.S. in 1996. Earlier in other countries and had probably been on the table for several years before that. Also it simply is not an issue in factory cars with the computers to deal with it. I run a shift cut feature on my gas car with a standalone and I cut the timing for .2sec. Shift is over and back to full power. Dual clutch transmissions also target the next gears rpm during the clutch disengagement. Very common strategies.
The opening of the k3 port does help a lot. It allows filling the k3 clutch at lower pressures faster. This prevents the pressure spike in the valve body that will prematurely release the b2 clutch making the flare worse.
Thanks, very useful information. Both by boxes worked without problems on previous cars, so with standalone controller and more power it really just needs power reduction during shift.
(02-06-2015, 05:38 PM)whipplem104 Actually most newer stuff is not. Physical size is an issue with doing this. And remember that the 722.6 was released in the U.S. in 1996. Earlier in other countries and had probably been on the table for several years before that. Also it simply is not an issue in factory cars with the computers to deal with it. I run a shift cut feature on my gas car with a standalone and I cut the timing for .2sec. Shift is over and back to full power. Dual clutch transmissions also target the next gears rpm during the clutch disengagement. Very common strategies.
The opening of the k3 port does help a lot. It allows filling the k3 clutch at lower pressures faster. This prevents the pressure spike in the valve body that will prematurely release the b2 clutch making the flare worse.
Thanks, very useful information. Both by boxes worked without problems on previous cars, so with standalone controller and more power it really just needs power reduction during shift.
(02-06-2015, 05:38 PM)whipplem104 Actually most newer stuff is not.
That's a vague and broad statement. The trans I mentioned, ZF 6HP26 is found in Rolls, BMW, Jag, Bentley, Rover, some Fords, Audi and more. Ford's 6R60/80 is a licensed copy of this trans. I strongly suspect that the GM 6L transmissions are also copies since they also only have a single one-way, the low one-way, only supply engine braking in 1st with the low/rev clutch applied (MAN1), are CAN controlled and built by Borg Warner, like the Ford transmissions. That's huge chunk of the newer transmissions out there.
When I said that this trans has all synchronized shifts, I was recalling info from a training course on the 6R60/80.
F150 WSM All gear shifts from 1st to 6th or from 6th to 1st are power-on overlapping shifts. That is, during the shift, one of the clutches must continue to transmit the drive at lower main pressure until the other clutch is able to accept the input torque.
The purpose of these shift elements is to carry out in-load shifts with no interruption to traction.
Similar statements are found in ZF 6hp26 WSM's
Quote: All shifts from 1st to 6th gears are power-on overlapping shifts. Overlapping shifts can be described as one of the clutches continuing to transmit drive at a lower main pressure until the next required clutch is able to accept the input torque.
Quote:Physical size is an issue with doing this.
6hp26 wiki page The ZF 6HP26 uses a Lepelletier epicyclic/planetary gearset, which can provide more gear ratios with significantly fewer components. This means the ZF 6HP26 is actually lighter than its 5-speed predecessors.
Quote:And remember that the 722.6 was released in the U.S. in 1996.
The E4od came out in '85. It was a business decision to make all shifts non-synchronized. I don't think Mercedes was limited by technical ability to make a fully non-synchronized transmission, it was just a dollars and cents call.
Quote:Also it simply is not an issue in factory cars with the computers to deal with it. I run a shift cut feature on my gas car with a standalone and I cut the timing for .2sec. Shift is over and back to full power.
A computer can't possibly fully mask the limitations of a non-synchronized shift. There is always a torque interruption and the quotes I left above indicate manufacturers are keen to this. Further, it's practice to leave the TCC applied during shifts to maximize fuel economy. I'm not saying it *can't* be done on a synchronized shift, but I've never seen it done.
When the 6r60/80 came out, it was the first time I ever saw an auto trans model with higher fuel economy on the window sticker than the same car with a 6 speed manual. Interrupting torque and unlocking the converter to accommodate a synchronized shift would not have made this possible.
raysorenson
02-07-2015, 10:37 AM #54(02-06-2015, 05:38 PM)whipplem104 Actually most newer stuff is not.
That's a vague and broad statement. The trans I mentioned, ZF 6HP26 is found in Rolls, BMW, Jag, Bentley, Rover, some Fords, Audi and more. Ford's 6R60/80 is a licensed copy of this trans. I strongly suspect that the GM 6L transmissions are also copies since they also only have a single one-way, the low one-way, only supply engine braking in 1st with the low/rev clutch applied (MAN1), are CAN controlled and built by Borg Warner, like the Ford transmissions. That's huge chunk of the newer transmissions out there.
When I said that this trans has all synchronized shifts, I was recalling info from a training course on the 6R60/80.
F150 WSM All gear shifts from 1st to 6th or from 6th to 1st are power-on overlapping shifts. That is, during the shift, one of the clutches must continue to transmit the drive at lower main pressure until the other clutch is able to accept the input torque.
The purpose of these shift elements is to carry out in-load shifts with no interruption to traction.
Similar statements are found in ZF 6hp26 WSM's
Quote: All shifts from 1st to 6th gears are power-on overlapping shifts. Overlapping shifts can be described as one of the clutches continuing to transmit drive at a lower main pressure until the next required clutch is able to accept the input torque.
Quote:Physical size is an issue with doing this.
6hp26 wiki page The ZF 6HP26 uses a Lepelletier epicyclic/planetary gearset, which can provide more gear ratios with significantly fewer components. This means the ZF 6HP26 is actually lighter than its 5-speed predecessors.
Quote:And remember that the 722.6 was released in the U.S. in 1996.
The E4od came out in '85. It was a business decision to make all shifts non-synchronized. I don't think Mercedes was limited by technical ability to make a fully non-synchronized transmission, it was just a dollars and cents call.
Quote:Also it simply is not an issue in factory cars with the computers to deal with it. I run a shift cut feature on my gas car with a standalone and I cut the timing for .2sec. Shift is over and back to full power.
A computer can't possibly fully mask the limitations of a non-synchronized shift. There is always a torque interruption and the quotes I left above indicate manufacturers are keen to this. Further, it's practice to leave the TCC applied during shifts to maximize fuel economy. I'm not saying it *can't* be done on a synchronized shift, but I've never seen it done.
When the 6r60/80 came out, it was the first time I ever saw an auto trans model with higher fuel economy on the window sticker than the same car with a 6 speed manual. Interrupting torque and unlocking the converter to accommodate a synchronized shift would not have made this possible.
Getting rid of the sprags actually is for economy purposes. Actually a lot of sprags are for overlap. For instance the front one in the 722.6 when it fails will cause a clutch to clutch type shift from 1-2nd gear. It keeps the k1 from free wheeling backwards when b1 is released before k1 can apply. The goal is to get rid of brake bands and anything else that has drag. Clutch pack clearances are set very loose on purpose also for the same reason. The computers do a pre fill on the clutch in preperation before the shift occurs. This is what most people complain about in manual modes. I hit the shifter and a second later it shifts. One solution is to run clutches in prefill almost all the time. Just enough pressure to keep the ports all filled up. Then when you are ready all you have to do is fill against free play and spring pressure.
I just re-read that ford wsm again. That is pretty much saying it is clutch to clutch. It has to keep the offcoming clutch on during the application of the oncoming clutch. Otherwise it you would have a stacking shift. Like a t400 or something of that generation. Were you simply just add another clutch pack for the next gear.
Also torque management does not mean that you are turning the engine off during shifts. Just reducing. Go to the link I provided for my facebook page. I have an actual engine torque and transmission reduced tq message in a datalog there. Remember engine rpms have to come down during a gear change and reducing engine output during a gear change is mostly for comfort for the occupants. Everyone does this at very low power outputs where it is totally not necessary. Mercedes starts tq reduction at anything above 100nm engine output. They also will add torque for engine braking downshifts for comfort as well.
whipplem104
02-07-2015, 11:04 AM #55Actually the GM 6l and ford equivalent are clutch to clutch transmissions. PCS does these as well. I am putting one in a 1971 C10 pickup truck right now. You can run these up to around 500 chp without torque reduction pretty successfully. As can you on the 722.6. After that you start having issues.
Getting rid of the sprags actually is for economy purposes. Actually a lot of sprags are for overlap. For instance the front one in the 722.6 when it fails will cause a clutch to clutch type shift from 1-2nd gear. It keeps the k1 from free wheeling backwards when b1 is released before k1 can apply. The goal is to get rid of brake bands and anything else that has drag. Clutch pack clearances are set very loose on purpose also for the same reason. The computers do a pre fill on the clutch in preperation before the shift occurs. This is what most people complain about in manual modes. I hit the shifter and a second later it shifts. One solution is to run clutches in prefill almost all the time. Just enough pressure to keep the ports all filled up. Then when you are ready all you have to do is fill against free play and spring pressure.
I just re-read that ford wsm again. That is pretty much saying it is clutch to clutch. It has to keep the offcoming clutch on during the application of the oncoming clutch. Otherwise it you would have a stacking shift. Like a t400 or something of that generation. Were you simply just add another clutch pack for the next gear.
Also torque management does not mean that you are turning the engine off during shifts. Just reducing. Go to the link I provided for my facebook page. I have an actual engine torque and transmission reduced tq message in a datalog there. Remember engine rpms have to come down during a gear change and reducing engine output during a gear change is mostly for comfort for the occupants. Everyone does this at very low power outputs where it is totally not necessary. Mercedes starts tq reduction at anything above 100nm engine output. They also will add torque for engine braking downshifts for comfort as well.
Using the 2-3 shift as an example: The forward clutch is applied in both gears. In second, the front carrier of the front simple planetary drives the "#3 sun gear" which is the rear sun gear of the Ravigneux in the rear of the trans. The "#2 sun gear", which is the front sun gear in the rear ravigneaux is held to the case by the intermediate clutch. When the shift to 3rd occurs, the only thing that changes is that the #2 sun is no longer held to the case and is instead driven by the front simple planetary carrier in the front of the trans along with the #3 sun gear. With 2 components of the rear ravigneaux being driven in the same direction at the same speed, the rear ravigneaux is locked in a 1:1 ratio, with all torque multiplication coming from the front simple planet.
*IF* the intermediate were to release the #2 sun before the direct clutch could drive it, you'd get a shift flare as the ravigneaux would go back into neutral/1st gear state with only one driven component and no held components until the low one way stopped overrunning.
*IF* the intermediate were to try to hold the #2 sun while the the direct clutch was attempting to drive it, what happens? The input shaft would get the braking force but not the output shaft. This is a variation of of a synchronized shift that does not result in the output shaft being locked to the case in the event of a component not releasing in time (the 722.6 problem), which could break traction or at least seriously interrupt driving force to the wheels. Instead, all that has to be done is that the direct clutch has to apply more force to the #2 sun than the intermediate clutches, forcing the intermediates to slip. This process is smoothed by torque reduction allowing the intermediate to loosen it's grip just enough to allow the direct to take over but not cause it to loosen so much that it slips back into 1st.
Hence the phrase "clutch over clutch". I found this confusing because clutch over clutch is applied to dual clutch gearboxes.
Not as cool as letting a one-way overrrun, but still works better than a lot of shitty synchronized shifts, like the old torqueflites. Will this trans work well with a primitive engine, say a 606 with a mechanical injection pump that cannot reduce torque? I've been eyeing one for an older AWD F150 project, in the event that the aftermarket ever supplies a CAN controller.
raysorenson
02-07-2015, 01:47 PM #56Okay, trying to wrap my head around this.
Using the 2-3 shift as an example: The forward clutch is applied in both gears. In second, the front carrier of the front simple planetary drives the "#3 sun gear" which is the rear sun gear of the Ravigneux in the rear of the trans. The "#2 sun gear", which is the front sun gear in the rear ravigneaux is held to the case by the intermediate clutch. When the shift to 3rd occurs, the only thing that changes is that the #2 sun is no longer held to the case and is instead driven by the front simple planetary carrier in the front of the trans along with the #3 sun gear. With 2 components of the rear ravigneaux being driven in the same direction at the same speed, the rear ravigneaux is locked in a 1:1 ratio, with all torque multiplication coming from the front simple planet.
*IF* the intermediate were to release the #2 sun before the direct clutch could drive it, you'd get a shift flare as the ravigneaux would go back into neutral/1st gear state with only one driven component and no held components until the low one way stopped overrunning.
*IF* the intermediate were to try to hold the #2 sun while the the direct clutch was attempting to drive it, what happens? The input shaft would get the braking force but not the output shaft. This is a variation of of a synchronized shift that does not result in the output shaft being locked to the case in the event of a component not releasing in time (the 722.6 problem), which could break traction or at least seriously interrupt driving force to the wheels. Instead, all that has to be done is that the direct clutch has to apply more force to the #2 sun than the intermediate clutches, forcing the intermediates to slip. This process is smoothed by torque reduction allowing the intermediate to loosen it's grip just enough to allow the direct to take over but not cause it to loosen so much that it slips back into 1st.
Hence the phrase "clutch over clutch". I found this confusing because clutch over clutch is applied to dual clutch gearboxes.
Not as cool as letting a one-way overrrun, but still works better than a lot of shitty synchronized shifts, like the old torqueflites. Will this trans work well with a primitive engine, say a 606 with a mechanical injection pump that cannot reduce torque? I've been eyeing one for an older AWD F150 project, in the event that the aftermarket ever supplies a CAN controller.
I agree that the terminology is a little confusing. But the basic idea is to let go of one clutch in a controlled fashion and apply the other in a controlled fashion. And depending on the ratios is how much slip you want in each clutch. The goal in the factory tunes is to achieve a zero torque push pull. Like a cvt transmission.
As far as using these newer transmissions with older cars PCS is doing this now. Like I said I am putting one in a carb. 1971 chevy c10 pickup. The transmission is mechatronic so what we do is build a torque map from tps and rpm to generate a torque table to transmit to the transmission computer via CAN. As far as the tcu is concerned it is operating in the factory car it was built for. We can also do tuning to the tcu for build up on the transmission. Right now this is really only for the dealers to do directly. It is not being sent out to the customers. It is just a little to complicated.
whipplem104
02-07-2015, 09:00 PM #57I assume you are talking about the zf,6l,6r in the above post. I have to admit I am not extremely well versed in the clutch and planet sets. I would have to go look over the info to refresh. But from what I remember what you are saying is correct. As I do tuning on transmissions more than anything else I concentrate on those issues. The basic gist is tune flare in and then tune it out.
I agree that the terminology is a little confusing. But the basic idea is to let go of one clutch in a controlled fashion and apply the other in a controlled fashion. And depending on the ratios is how much slip you want in each clutch. The goal in the factory tunes is to achieve a zero torque push pull. Like a cvt transmission.
As far as using these newer transmissions with older cars PCS is doing this now. Like I said I am putting one in a carb. 1971 chevy c10 pickup. The transmission is mechatronic so what we do is build a torque map from tps and rpm to generate a torque table to transmit to the transmission computer via CAN. As far as the tcu is concerned it is operating in the factory car it was built for. We can also do tuning to the tcu for build up on the transmission. Right now this is really only for the dealers to do directly. It is not being sent out to the customers. It is just a little to complicated.
whipplem104
03-11-2015, 08:16 AM #58So a little more on topic for this forum. I will be doing a .6 swap into a 95 e300d here shortly. It will start off with the stock n/a engine but will be getting a turbo motor built for it. etc. The customers goals are pretty high. So I should have some pretty solid maps built for these applications in the future. This will be a mildly built transmission as well. I will share the results as it progresses and take a few pictures of the install.
For those of you running this setup. This would work on any firmware version but will be easier to tune with the 2.37.5 firmware as you can see the ratio detection. On the earlier versions you would want to monitor speed 2 and speed 3 depending on the shift you are making.
whipplem104
03-15-2015, 01:19 PM #59Working on a new pressure control setup for these. I am running a two stage pressure control by activating the cal. B for a timed period then switching to cal A for the 2nd half. So far very cool as I can run two different line pressure tables and two different accum. pressure tables for the shifts. Much closer to what the factory does. I posted some logs and info on facebook. And the setup procedure. https://www.facebook.com/pages/Sound-German-Automotive/213743525471191
For those of you running this setup. This would work on any firmware version but will be easier to tune with the 2.37.5 firmware as you can see the ratio detection. On the earlier versions you would want to monitor speed 2 and speed 3 depending on the shift you are making.
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