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hellenic vanagon
Samba Member
Joined: December 28, 2007
Posts: 283
Location: ATHENS GREECE
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 Posted: Thu Nov 09, 2017 3:42 pm Post subject: Re: Syncro “AWD” Capabilty |
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It seems that documents like this:
have no validity for some persons here...
After that I quit.
Thank you for your time. |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Thu Nov 09, 2017 3:55 pm Post subject: Re: Syncro “AWD” Capabilty |
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| davevickery wrote: |
It looks like somne of those guys didn't get the memo on the proper test procedeure. I love the blue van with jacks.
This seems to show that no two vans are alike. Just another magical quality of the syncro. |
The vans would act alike with a new tested VC, but not with overused/broken units. |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Thu Nov 09, 2017 4:04 pm Post subject: Re: Syncro “AWD” Capabilty |
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| hellenic vanagon wrote: |
| IdahoDoug wrote: |
Sure, I can appreciate that. But its being stated without that qualifying aspect, assigning magical qualities to the VC. Same with the VC pulling through corners, providing handling a sports car cannot compete with, and handles uncontrollably in 2WD, etc. It is hard to have a discussion when so much bandwidth is given over to hyperbole. Especially because here on Samba that type of unqualified belief system about the VC and Syncro has been in place for a long time and clouded reasoned discussions. So when a reasoned discussion about a cool device breaks out, it makes it difficult to take the conversation seriously when the well informed "The VC pulls everywhere, all the time" crowd doesn't police its own.
I doubt I am the only one who feels this way - I just happen to have made the observation and asked for some relief. Next we will hear the Syncro helps men's hair grow back, and riding in one cures the common cold. |
After all these I dare to say:
you have never drove a 2wd Vanagon vs a Syncro Vanagon near their limits.
Or, much more, a 2wd Syncro vs a 4wd Syncro at the limit.
A 2wd car with no traction control, no esc, no abs and with wrong suspension adjustments, as it is a 2wd Syncro.
And this is "cheerleading". |
I am driving my Syncro on limits since long time mostly in 2wd mode.
There are no wrong suspension adjustments. breaks work perfect.
I think traction control, esc, abs and 4wd on pavement is for ladys. |
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hellenic vanagon
Samba Member
Joined: December 28, 2007
Posts: 283
Location: ATHENS GREECE
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| Posted: Thu Nov 09, 2017 4:10 pm Post subject: Re: Syncro “AWD” Capabilty |
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| Waldi wrote: |
| hellenic vanagon wrote: |
| IdahoDoug wrote: |
Sure, I can appreciate that. But its being stated without that qualifying aspect, assigning magical qualities to the VC. Same with the VC pulling through corners, providing handling a sports car cannot compete with, and handles uncontrollably in 2WD, etc. It is hard to have a discussion when so much bandwidth is given over to hyperbole. Especially because here on Samba that type of unqualified belief system about the VC and Syncro has been in place for a long time and clouded reasoned discussions. So when a reasoned discussion about a cool device breaks out, it makes it difficult to take the conversation seriously when the well informed "The VC pulls everywhere, all the time" crowd doesn't police its own.
I doubt I am the only one who feels this way - I just happen to have made the observation and asked for some relief. Next we will hear the Syncro helps men's hair grow back, and riding in one cures the common cold. |
After all these I dare to say:
you have never drove a 2wd Vanagon vs a Syncro Vanagon near their limits.
Or, much more, a 2wd Syncro vs a 4wd Syncro at the limit.
A 2wd car with no traction control, no esc, no abs and with wrong suspension adjustments, as it is a 2wd Syncro.
And this is "cheerleading". |
I am driving my Syncro on limits since long time mostly in 2wd mode.
There are no wrong suspension adjustments. breaks work perfect.
I think traction control, esc, abs and 4wd on pavement is for ladys. |
What about this:
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raoul mitgong
Samba Member
Joined: July 05, 2009
Posts: 1338
Location: Denver, CO
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| Posted: Thu Nov 09, 2017 4:19 pm Post subject: Re: Syncro “AWD” Capabilty |
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Jon wrote:
| Quote: |
glad to hear your VC still scrubs when parking. I would choose to decouple in that situation.
It is a macro of what happens on dry curves.. scrubbing..
scrubbing is not pulling |
I guess I consider scrubbing a small price to pay for the benefits. I don't consider slow scrubbing a safety concern and my van doesn't seem to mind it. A decoupler might be a decent upgrade if I did a lot of shopping.
This is not a macro of what happens on dry curves though. You would not be turning your steering wheel more than about 30 degrees at 60 mph in a curve. 90 degrees would roll you or ditch you in seconds. I'm thinking at least 180 degrees at the steering wheel is needed to park around here.
I agree that scrubbing is not pulling. My previous posts should be clear that I have never stated nor inferred that.
_________________
84 Westy with a 2.1 (Groover)
86 Tintop Syncro (Crow)
86 Tintop Syncro to Westy project (Tom Servo)
91 Westy (Only the top 12 inches of this van (a burn victim)) |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Thu Nov 09, 2017 4:26 pm Post subject: Re: Syncro “AWD” Capabilty |
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| raoul mitgong wrote: |
| Quote: |
| Just looking for someone besides iDoug and me, to try and explain it to people who don't think a decoupler is necessary with a VC. |
"Necessary"? Careful, iDoug might accuse you of hyperbole.
226,000 miles coupled on my drivetrain with no VC or associated tranny failure.
Sodo's hypothesis on reducing the load on the the R&P if coupled deserves discussion. Sodo's temp readings of coupled and uncoupled are very interesting. Testing a hypothesis, that's science!
As a mechanical engineer who wants his Syncro(s) to last, I'm more interested in the facts than winning an internet conversation.
If any of the math or "facts" presented can be shown to be false, awesome. More of that please.
-d |
With over 200k miles without decoupler your VC is way off the specs. If you are lucky it is softer due to gear oil inside.
Messureing the temp on the box says nothing if not done in all driving situations.
If you drive up or downhill with alot of 180 turns, or in a city, you will sure not save your r+p without decoupling.
Infact driving in this situations 10 miles coupled will load your box much more than driving 1000 miles decoupled straight on.
If the driving coupled with the Syncro would save the box they should last longer than 2wd boxes. Do they ?
Or how can my box last for 200k with still good bearings pulling heavy trailers ? I am driving always decoupled.
Where do you think come the 59 degrees from on Nicos front diff ?
Burning sensless fuel. Putting sensless load on both boxes. |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Thu Nov 09, 2017 4:32 pm Post subject: Re: Syncro “AWD” Capabilty |
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| hellenic vanagon wrote: |
| Waldi wrote: |
| hellenic vanagon wrote: |
| IdahoDoug wrote: |
Sure, I can appreciate that. But its being stated without that qualifying aspect, assigning magical qualities to the VC. Same with the VC pulling through corners, providing handling a sports car cannot compete with, and handles uncontrollably in 2WD, etc. It is hard to have a discussion when so much bandwidth is given over to hyperbole. Especially because here on Samba that type of unqualified belief system about the VC and Syncro has been in place for a long time and clouded reasoned discussions. So when a reasoned discussion about a cool device breaks out, it makes it difficult to take the conversation seriously when the well informed "The VC pulls everywhere, all the time" crowd doesn't police its own.
I doubt I am the only one who feels this way - I just happen to have made the observation and asked for some relief. Next we will hear the Syncro helps men's hair grow back, and riding in one cures the common cold. |
After all these I dare to say:
you have never drove a 2wd Vanagon vs a Syncro Vanagon near their limits.
Or, much more, a 2wd Syncro vs a 4wd Syncro at the limit.
A 2wd car with no traction control, no esc, no abs and with wrong suspension adjustments, as it is a 2wd Syncro.
And this is "cheerleading". |
I am driving my Syncro on limits since long time mostly in 2wd mode.
There are no wrong suspension adjustments. breaks work perfect.
I think traction control, esc, abs and 4wd on pavement is for ladys. |
What about this:
|
Thats nothing.
As long the tires looks good, everything is within the specs.
30+-30 is the same as 20+-20 |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Thu Nov 09, 2017 4:47 pm Post subject: Re: Syncro “AWD” Capabilty |
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| Jon_slider wrote: |
| raoul mitgong wrote: |
| 226,000 miles coupled on my drivetrain with no VC or associated tranny failure. |
have you confirmed that your VC has not failed in the open position?
Ive had Two VCs that gave no resistance to parking, but they also turned out to give no lockup and had to be replaced.
The test I recommend is putting a 2x4 in front of the front wheels, and jack up one rear wheel on a rolling dolly. Do not lock the rear diff.
At idle in granny gear, a stock spec VC should NOT climb over the 2x4. This proves if a VC is not overly aggressive, and may not require a decoupler.
Above idle, the VC should lock up, and the front wheels should climb over the 2x4. This proves the VC is capable of locking up, and may benefit from decoupling on dry curves.
When you do the test, you may be surprised to see that the rear wheels spin much more than 5% faster than the front, some vans will rotate more than one full turn of the rear tire, before climbing the 2x4. |
This tests show not if a VC is within specs. This can only be tested on a VC test bench.
A VC which do not transfer torque on idle is trash. |
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raoul mitgong
Samba Member
Joined: July 05, 2009
Posts: 1338
Location: Denver, CO
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| Posted: Thu Nov 09, 2017 9:01 pm Post subject: Re: Syncro “AWD” Capabilty |
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| hellenic vanagon wrote: |
It seems that documents like this:
have no validity for some persons here...
After that I quit.
Thank you for your time. |
Hellenic,
Can we get some translation ont the two curves and x y axis?
Thanks,
-d
_________________
84 Westy with a 2.1 (Groover)
86 Tintop Syncro (Crow)
86 Tintop Syncro to Westy project (Tom Servo)
91 Westy (Only the top 12 inches of this van (a burn victim)) |
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raoul mitgong
Samba Member
Joined: July 05, 2009
Posts: 1338
Location: Denver, CO
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| Posted: Thu Nov 09, 2017 9:07 pm Post subject: Re: Syncro “AWD” Capabilty |
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| Waldi wrote: |
| raoul mitgong wrote: |
| Quote: |
| Just looking for someone besides iDoug and me, to try and explain it to people who don't think a decoupler is necessary with a VC. |
"Necessary"? Careful, iDoug might accuse you of hyperbole.
226,000 miles coupled on my drivetrain with no VC or associated tranny failure.
Sodo's hypothesis on reducing the load on the the R&P if coupled deserves discussion. Sodo's temp readings of coupled and uncoupled are very interesting. Testing a hypothesis, that's science!
As a mechanical engineer who wants his Syncro(s) to last, I'm more interested in the facts than winning an internet conversation.
If any of the math or "facts" presented can be shown to be false, awesome. More of that please.
-d |
With over 200k miles without decoupler your VC is way off the specs. If you are lucky it is softer due to gear oil inside.
Messureing the temp on the box says nothing if not done in all driving situations.
If you drive up or downhill with alot of 180 turns, or in a city, you will sure not save your r+p without decoupling.
Infact driving in this situations 10 miles coupled will load your box much more than driving 1000 miles decoupled straight on.
If the driving coupled with the Syncro would save the box they should last longer than 2wd boxes. Do they ?
Or how can my box last for 200k with still good bearings pulling heavy trailers ? I am driving always decoupled.
Where do you think come the 59 degrees from on Nicos front diff ?
Burning sensless fuel. Putting sensless load on both boxes. |
All good points Waldi. Do you think more or less wear would occur rearward of the VC coupled or uncoupled when driving long straight USA type interstate highways?
-d
_________________
84 Westy with a 2.1 (Groover)
86 Tintop Syncro (Crow)
86 Tintop Syncro to Westy project (Tom Servo)
91 Westy (Only the top 12 inches of this van (a burn victim)) |
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WLD*WSTY
Samba Member
Joined: November 04, 2009
Posts: 438
Location: Arizona
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| Posted: Thu Nov 09, 2017 11:35 pm Post subject: Re: Syncro “AWD” Capabilty |
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Perhaps someone can enlighten me...
Quite a few cars use or have used viscous couplers. Do they have such problems with their VCs that they feel the need for solid shafts and decouplers too? Have the Volvo, Subaru, and Land Rover forums had these same sort of discussions? Did the Toyota Celica GT-Four and RAV Four or the AMC Eagle suffer from the same (alleged) deficiencies? Shall I cancel my order for an Audi R8? Sell the Lambo?
Help me out here.
_________________
'82 SyncroWesty, the first ever conversion.'06 Subaru 2.5L |
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IdahoDoug
Samba Member
Joined: June 12, 2010
Posts: 10250
Location: N. Idaho
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| Posted: Fri Nov 10, 2017 12:15 am Post subject: Re: Syncro “AWD” Capabilty |
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Westy,
Viscous Couplers are an effective powertrain component but I think the Syncro is fairly unique in that the power/engine starts in the rear of the vehicle and is expected to make its way through a VC to the front wheels (which in general road use, already turn more than the rears) so its ability to transmit power is perhaps somewhat limited by comparison. Most cars are front engine, front wheel drive and there a VC to drive rear wheels will not bind on sharp steering or parking, or generate heat or braking forces on curves - all Syncro shortcomings.
Still others have been used as actual differentials in FWD cars to inhibit torque steer, etc. I think the Nissan Sentra R Type maybe.
But no, I don't think other makes use the magic VC that Vanagons have.
Hellenic - when you translate the graph for Raoul it would be good to know the axis labels, and what kind of vehicle it was and what type of 4WD system and engine it had, and perhaps even some curve diameter info. It kinda looks like a steering angle vs lateral G chart I'm used to seeing but the steering angle numbers look a tad higher than I'm used to seeing.
_________________
1987 2WD Wolfsburg Vanagon Weekender "Mango", two fully locked 80 Series LandCruisers. 2017 Subaru Outback boxer. 1990 Audi 90 Quattro 20V with rear locking differential, 1990 burgundy parts Vanagon. 1984 Porsche 944, 1988 Toyota Supra 5 speed targa, 2002 BMW 325iX, 1982 Toyota Sunrader |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Fri Nov 10, 2017 1:25 am Post subject: Re: Syncro “AWD” Capabilty |
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| raoul mitgong wrote: |
| Waldi wrote: |
| raoul mitgong wrote: |
| Quote: |
| Just looking for someone besides iDoug and me, to try and explain it to people who don't think a decoupler is necessary with a VC. |
"Necessary"? Careful, iDoug might accuse you of hyperbole.
226,000 miles coupled on my drivetrain with no VC or associated tranny failure.
Sodo's hypothesis on reducing the load on the the R&P if coupled deserves discussion. Sodo's temp readings of coupled and uncoupled are very interesting. Testing a hypothesis, that's science!
As a mechanical engineer who wants his Syncro(s) to last, I'm more interested in the facts than winning an internet conversation.
If any of the math or "facts" presented can be shown to be false, awesome. More of that please.
-d |
With over 200k miles without decoupler your VC is way off the specs. If you are lucky it is softer due to gear oil inside.
Messureing the temp on the box says nothing if not done in all driving situations.
If you drive up or downhill with alot of 180 turns, or in a city, you will sure not save your r+p without decoupling.
Infact driving in this situations 10 miles coupled will load your box much more than driving 1000 miles decoupled straight on.
If the driving coupled with the Syncro would save the box they should last longer than 2wd boxes. Do they ?
Or how can my box last for 200k with still good bearings pulling heavy trailers ? I am driving always decoupled.
Where do you think come the 59 degrees from on Nicos front diff ?
Burning sensless fuel. Putting sensless load on both boxes. |
All good points Waldi. Do you think more or less wear would occur rearward of the VC coupled or uncoupled when driving long straight USA type interstate highways?
-d |
I can awnser this just from my point driving allways in 2wd and not seeing more wear.
I have not driven a bench tested VC always coupled over 12 years and 300k km.
My self made VC still works like on the 1st day.
The VC, if allways in use, will suck oil over time.
Or it gets overheated because of bad tires, exessive offroad use, and destroy the seal rings.
This is a part which has be changed every 100k depends on using.
As for the other cars that use VCs, do you know any that run over 30 years ?
ID, the way the Syncro has the VC is exactly the good part of it.
Driven the rear wheels more than the front ones, mechanicaly, without any electrical assistance, like the new cars have to get 60/40 on the street.
Now the question, how many of yue have ever driven a new tested within VW specs VC ? |
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hellenic vanagon
Samba Member
Joined: December 28, 2007
Posts: 283
Location: ATHENS GREECE
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| Posted: Fri Nov 10, 2017 2:18 am Post subject: Re: Syncro “AWD” Capabilty |
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| IdahoDoug wrote: |
Westy,
Viscous Couplers are an effective powertrain component but I think the Syncro is fairly unique in that the power/engine starts in the rear of the vehicle and is expected to make its way through a VC to the front wheels (which in general road use, already turn more than the rears) so its ability to transmit power is perhaps somewhat limited by comparison. Most cars are front engine, front wheel drive and there a VC to drive rear wheels will not bind on sharp steering or parking, or generate heat or braking forces on curves - all Syncro shortcomings.
Still others have been used as actual differentials in FWD cars to inhibit torque steer, etc. I think the Nissan Sentra R Type maybe.
But no, I don't think other makes use the magic VC that Vanagons have.
Hellenic - when you translate the graph for Raoul it would be good to know the axis labels, and what kind of vehicle it was and what type of 4WD system and engine it had, and perhaps even some curve diameter info. It kinda looks like a steering angle vs lateral G chart I'm used to seeing but the steering angle numbers look a tad higher than I'm used to seeing. |
1)Really?
PORSCHE with VCT:
(click to enlarge)
Supported by edl.
Here the vct replaces the, previously used, central epicyclic differential.
2)In my previous posts there is the link with the white paper in which is explained "what type of 4wd system and engine it had".
3)If there are difficulties in translation from the German language make an update to your browser. |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Fri Nov 10, 2017 3:23 am Post subject: Re: Syncro “AWD” Capabilty |
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Nice explanation with the Porsche example Helenic.
The only thing is to remember, the VC system only works perfect if within the specs.
But in the world of 30 year old Syncros and selfmade Viscos the decoupler does its job.
Especialy with harder adjusted VCs for better offroad use.
Edit:
Would be nice to hear the statement of old VW engineers why they have designed the decoupler for the Syncro. |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Fri Nov 10, 2017 3:36 am Post subject: Re: Syncro “AWD” Capabilty |
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| IdahoDoug wrote: |
...
(which in general road use, already turn more than the rears) so its ability to transmit power is perhaps somewhat limited by comparison.
...
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Missed this part.
In general mode the rear turn more than the front due to slip. |
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hellenic vanagon
Samba Member
Joined: December 28, 2007
Posts: 283
Location: ATHENS GREECE
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| Posted: Fri Nov 10, 2017 4:17 am Post subject: Re: Syncro “AWD” Capabilty |
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| Waldi wrote: |
Nice explanation with the Porsche example Helenic.
The only thing is to remember, the VC system only works perfect if within the specs.
But in the world of 30 year old Syncros and selfmade Viscos the decoupler does its job.
Especialy with harder adjusted VCs for better offroad use.
Edit:
Would be nice to hear the statement of old VW engineers why they have designed the decoupler for the Syncro. |
Thank you.
Why the service, (replace or repair), of a part, after 30 years of hard use, may be considered as a problem?
The 4x4 cars, in general, need much more.
And the Syncro, (esp. the (t25) t3), is so much respected that it is ready for another 30 years turn.
Did you see the youtube Syncro new generation, (of proud owners)? |
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Waldi
Samba Member
Joined: February 28, 2014
Posts: 1752
Location: Germany
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| Posted: Fri Nov 10, 2017 5:08 am Post subject: Re: Syncro “AWD” Capabilty |
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| hellenic vanagon wrote: |
| Waldi wrote: |
Nice explanation with the Porsche example Helenic.
The only thing is to remember, the VC system only works perfect if within the specs.
But in the world of 30 year old Syncros and selfmade Viscos the decoupler does its job.
Especialy with harder adjusted VCs for better offroad use.
Edit:
Would be nice to hear the statement of old VW engineers why they have designed the decoupler for the Syncro. |
Thank you.
Why the service, (replace or repair), of a part, after 30 years of hard use, may be considered as a problem?
The 4x4 cars, in general, need much more.
And the Syncro, (esp. the (t25) t3), is so much respected that it is ready for another 30 years turn.
Did you see the youtube Syncro new generation, (of proud owners)? |
No, not a problem, it should be a pleasure 
But in the reality ppl dont have money, or possibility, or both to get a new VC.
Mostly you see ppl whine and complain about 30 year old broken parts and expensive maintainance.
Edit:
Owners here in EU have some choice.
https://www.vwt3.at/index.php?/topic/46597-visco-werkstatt-kern-goes-busfest-gb/
https://vw-kern.at/welcome
I repair only boxes for ppl with a new VC or one from Kern, or decoupler. |
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hellenic vanagon
Samba Member
Joined: December 28, 2007
Posts: 283
Location: ATHENS GREECE
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| Posted: Fri Nov 10, 2017 5:46 am Post subject: Re: Syncro “AWD” Capabilty |
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| Waldi wrote: |
| hellenic vanagon wrote: |
| Waldi wrote: |
Nice explanation with the Porsche example Helenic.
The only thing is to remember, the VC system only works perfect if within the specs.
But in the world of 30 year old Syncros and selfmade Viscos the decoupler does its job.
Especialy with harder adjusted VCs for better offroad use.
Edit:
Would be nice to hear the statement of old VW engineers why they have designed the decoupler for the Syncro. |
Thank you.
Why the service, (replace or repair), of a part, after 30 years of hard use, may be considered as a problem?
The 4x4 cars, in general, need much more.
And the Syncro, (esp. the (t25) t3), is so much respected that it is ready for another 30 years turn.
Did you see the youtube Syncro new generation, (of proud owners)? |
No, not a problem, it should be a pleasure
But in the reality ppl dont have money, or possibility, or both to get a new VC.
Mostly you see ppl whine and complain about 30 year old broken parts and expensive maintainance.
Edit:
Owners here in EU have some choice.
https://www.vwt3.at/index.php?/topic/46597-visco-werkstatt-kern-goes-busfest-gb/
https://vw-kern.at/welcome
I repair only boxes for ppl with a new VC or one from Kern, or decoupler. |
Very interesting. |
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Pcforno
Samba Member
Joined: October 14, 2014
Posts: 575
Location: Santa Fe, nm
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| Posted: Fri Nov 10, 2017 6:23 am Post subject: Re: Syncro “AWD” Capabilty |
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Yes - I can tell you that my original VC looked like the videos posted earlier where it took a bit of spin to engage. When I redid my engine and transaxle I put in a rebuilt VC (German transaxle in bend, I think). It now passes the 2x4 test with zero rear wheel spin. It’s pretty much instant engagement. And no, it’s not locked all the time - I’m able to make tight turns without crazy wheel scrubbing.
I’ve done similar tests on my wife’s 2003 Subaru which has a center differential plus VC, and the Subaru’s engaged way slower than the van with a quite a bit more wheelspin drama. |
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