Betty blows another Tranny

Jon_slider · Posted: Mon Dec 03, 2012 5:37 pm Post subject:

I added these pics one page back also, this is an alternate design for a Syncro brace. I hope to receive plans for this version in a few weeks, will share..

Image may have been reduced in size. Click image to view fullscreen.

The person who makes this type

is building a few in a couple weeks, Private Message me if you want to get in on the order.
_________________
My Soapboxes: Inflation; Handling; Gearing; Decoupling; Swepco

pedrokrusher · Posted: Mon Dec 03, 2012 5:54 pm Post subject:

gears · Posted: Tue Dec 04, 2012 7:30 am Post subject:

Our transaxles do not suffer from longitudinal "case flex". The pictured braces were not made to address "case flex".

The brace provides a secondary path for vibrations, pulses .. whatever it is about 5 cylinders that causes damage within our transaxles. The stiffer the brace, the better job it does at transmitting vibrations.

According to South African enthusiasts, the brace is effective at delivering those pulse/vibrations to the front of the transaxle slightly out-of-phase with those passing through the main body.
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

insyncro · Posted: Tue Dec 04, 2012 7:39 am Post subject:

gears · Posted: Tue Dec 04, 2012 7:54 am Post subject:

According to those who built it, the brace is doing its job as a dampener. This enters an area that I know little about (although I have some knowledge about transaxle internals and performance mods). What I can tell you with certainty is that Betty's problems aren't because the main case is "flexing".
_________________
aka Pablo, Geary
9.36 @ 146 in '86 Hot & Sticky
'90 Syncro Westy SVX
'87 Syncro GL 2.5
https://guardtransaxle.com

danfromsyr · Posted: Tue Dec 04, 2012 8:00 am Post subject:

they're just trying to change the tone of the "drum" to accoustic waves..
_________________

insyncro · Posted: Tue Dec 04, 2012 8:13 am Post subject:

Thanks Guys....got it.

kgold708 · Posted: Tue Dec 04, 2012 11:02 am Post subject:

Jon_slider · Posted: Tue Dec 04, 2012 11:09 am Post subject:

archiving this post from

http://autos.groups.yahoo.com/group/SyncroSA/message/21375
Re: Looking for engine/gearbox brace
Posted By:
derekbezuide...
Mon Dec 3, 2012 11:16 pm |
Options

Hi JonS
Just some info that might assist you in improving the reliability of the 5 cyl
Syncro. When VW of SA developed the 2.6 - 5 cyl T3 2wd they had to make various
changes to reduce the 2nd order vibration and gearbox as well as engine oil
temperature levels. These included the following: Engine oil cooler, stiffer
clutch housing, stiffer bracket between the lower part of the clutch housing and
engine block, Stiffening bracket above the gearbox, oil splash plates for the
crownwheel and 5th gear, crownwheel & pinion set with a 7 tooth pinion gear,
fully synthetic gear oil and softer gearbox monting. When we first fitted 5 cyl
engines to the Syncro we found that it had higher vibration levels than the 2wd
drive as the gearbox is both heavier and longer which means a lower resonance
frequency. The bracket which we developed (shown in the attachment archives on
the site dated March 24 2011) is stiffer that the std bracket and reduced
vibration levels to close to the 5spd 2wd levels. (measured at the front end of
the gearbox). The gear oil temperature was also significantly higher than in the
2wd . We measured the oil temperature of different gearoils on a long flat road
with a trailer at max speed to compare the oils. The oil that gave the best
results was Engen SPL which has a GL5+ rating and is specifically developed for
transaxels with hypoid differentials. (Audi Motorsport used this oil in their
Turbo rally and racing vehicles in the 90's). By adding a PTFE additive to this
oil, we saw a further reduction in max oil temperatures. The temperature of the
GL4 rated oils did not stabilize and continued to slowly rise. A GL5 75w-90
synthetic oil developed for transaxle available in the US like Liquimoly or
Mobil should give similar results. From getting a maximum of 20 000 km on the
transaxle we now have 5cyl Syncro's with over 150 000 km's. The only other
concern I have is that the 5cyl diesel would have a higher tortional vibration
than the petrol, so using a duel mass flywheel might also be something to
consider but you would need to add a spacer plate between the engine and the
clutch housing. Also fit a temperature sensor to the gearbox to monitor oil
temperatures.
_________________
My Soapboxes: Inflation; Handling; Gearing; Decoupling; Swepco

syncrogreg · Posted: Tue Dec 04, 2012 11:49 am Post subject:

http://www.caranddriver.com/features/the-future-dims-for-the-five-cylinder-engine-feature
_________________
conversions: www.boxeer.com Common rail TDI and NOW PDK transmissions!!

travel pictures:
http://instagram.com/crepeattack/

- the Pastis build: http://www.thesamba.com/vw/forum/viewtopic.php?t=434656&highlight=subaru+diesel

Jon_slider · Posted: Tue Dec 04, 2012 1:19 pm Post subject:

a series of photos of my transaxle cooler in development by AATransaxle
https://picasaweb.google.com/Darylspics/JonSliderTrans#

includes a crack at the pinion bearing support (correct terminology?), see
https://picasaweb.google.com/Darylspics/JonSliderTrans#5818169328963573346
that I attribute to being a jerk at the beach. If so, Lost Coast was a very expensive vehicle recovery seminar. Got the Tranny-Shirt

Im looking at this Bush Wench as an alternative

Link

followed by one of these
Bush showers
http://bushranger.com.au/hot_water_shower.php

_________________
My Soapboxes: Inflation; Handling; Gearing; Decoupling; Swepco

insyncro · Posted: Tue Dec 04, 2012 4:53 pm Post subject:

Audi 90 quattro IMSA GTO with Hans Stuck at the wheel in 1989 at Lime Rock Park, CT.
5-cylinder-turbo and around 600hp or a little bit more but no wheel spin.

Just sharing.
I know, its a gasser. Cool

D Clymer · Posted: Tue Dec 04, 2012 5:19 pm Post subject:

That Car and Driver article that Greg linked has good information regarding the 2nd order vibrations present in the 5 cylinder configuration. Most of that is regurgitated from a Car and Driver article published in 1977 at the time the first Audi 5000 was launched. In addition to the information on Henry Ford's experiments with 5 cylinders, it also described the way Audi dealt with the vibration problems. They did two things. First, they did extensive analysis of the 2nd order forces and carefully reinforced the transmission bellhousing and engine block (flywheel end) to create rigid structures. The remaining forces they dealt with by using large volume rubber engine mounts. If you look at 5 cylinder Audi motor mounts they are much larger than the typical mount from 1977.

With this in mind, I think it is very important to retrofit the force damper (longitudinal brace) to the 094 transmission. Theoretically it should be there since the 094 case was never webbed to accomodate a 5 cylinder. I find it even more promising that Jon's South African correspondent mentions greatly enhanced durability. The only remaining doubt I have regarding longevity is that the TDI has an extremely long stroke: 95.5mm compared to 86.4 or 92.8 for the petrol engines. This combined with the fact that the engine is a diesel and by nature vibrates more makes me wonder if the damper will be enough. Also, the engine puts out a tremendous amount of torque which is probably still too much for a Syncro tranny. I hope it holds up, though.

David

D Clymer · Posted: Tue Dec 04, 2012 5:32 pm Post subject:

I forgot to mention that I have no doubt that the Audi 5 cylinder does have some unique vibration characteristics. We have had several Audi 5 cylinder cars in my family and I remember my mom's 1991 Audi 100 with 2.3 5 cylinder would vibrate the Venetion blinds in my upstairs bedroom whenever someone would start up and back the Audi out of the garage. None of our other cars (including a 1987 Vanagon Wink

) affected the blinds at all.

The 5 cylinder is an interesting engine. They can be very smooth in the mid-range, but they get pretty thrashy at high-rpms. They do sound great, though. I think the biggest problem they face conceptually is that they cannot have a balance shaft added due to the location the balance shaft would have to be placed at. This puts them at a disadvantage in this day and age because a good inline 4 with balance shafts is now actually smoother than an inline 5. In the old days the 5 cylinder's primary trump was that it was smoother than an inline four. My primary car is a 2010 GTI with the 4 cylinder 2.0 TSI engine. That engine is a lot smoother and unobtrusive than the 2.5 5 cylinder used in base model Jettas, Passats, and Golfs.

I do hope the 5 cylinder survives. I've always liked the unique sound of them.

D

Jon_slider · Posted: Tue Dec 11, 2012 9:16 am Post subject:

a little more info from SA correspondents

Hi John
I will try to help were i can. I have never owned or built a 5 cylinder TDI syncro before. I did build a 5 cylinder TD about 10 years ago and have had a few 5 cylinder petrols. I mainly use the 4 cylinder TDI's in my vans.
The brace i have just fitted to Deans van is for a 2.6 5 cylinder petrol. If this brace is not fitted to the 5 cylinder petrol
engined vans the gearboxes suffer from oil leaks and in some extreme cases gearbox fractures in the diff casing.
A lot of this is to do with were the engine mounts sit compared to the length of the engine. On acceleration it puts a
lot of pulling force across the gearbox spine. There is also a degree of twisting force appield. A third mount can also be fitted
at the rear as Audi did in the factory. These all help with case strain.
I use decouplers on my vans as-well but had a VC fitted to my last doka and standard 6.136 box with 235 85 16 tires. I initially
didnt have much hope for the box but it lasted me over 3 years with no problems and is still going strong. Not rebuilt either.
This was with lots of off road use. I do put this down to spreading the load even under normal conditions.
I do also use a sports VC with my decouplers so i do have a little shock adsorption in the drive train.
Non of this may be relevant to your gearbox problem but may help.
I will send you a photo later.
Cheers for now
Russel

===
Hi Jon
I unfortunetly do not have a built up brace at the moment, but can send you my drawings around christmas when I get back home. I have read some of the comments on the forum. When we first fitted the 5 cyl to the T3 transaxels, we straingauged the complete engine and transmission cassings to see what was happening. The 5 cyl motor tends to rock horizontily around where the engine mountings are on the block. The gearbox then flexes around the clutchhousing/ differential area, as this is a weak area of the cassing design. Tha brace then stiffens this area which affectively shifts the reasonance frequency of the engine/ gearbox unit higher. If I recall correctly it goes from around 125Hz to 180Hz. In second order this means moving the peak vibrations up from 3700 rpm to 5400 rpm
Thanks
Derek

===

I have also posted brace photos and these
SA letters here:
http://www.thesamba.com/vw/forum/viewtopic.php?p=6384081#6384081
_________________
My Soapboxes: Inflation; Handling; Gearing; Decoupling; Swepco

pedrokrusher · Posted: Tue Dec 11, 2012 12:24 pm Post subject:

Jon_slider · Posted: Tue Dec 11, 2012 12:47 pm Post subject:

SyncroGhia · Posted: Tue Dec 11, 2012 3:05 pm Post subject:

I'm going to look into having the petrol tank modified to allow the brace to be fitted.

I need to either find some very good plastic glue or a company that knows all about modifying plastic housings!

MG
_________________
T3 Syncro 16 S6 Westfalia Limey SOLD
T3 Syncro 6x6 SOLD
T3 RS6 Bluestar
T3 Tristar Syncro 16 SOLD
T3 Tristar Syncro RHD SOLD


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