07-22-2012, 04:48 PM
|
|
Registered User
|
|
Join Date: Mar 2008
Location: Austin Texas via So. Calif.
Posts: 246
|
|
Sachs Pressure Plate Failure
As fore told by Paul Spruell my 2 liter OEM Sachs presure plate torque straps failed in a very alarming manner. Apparently in the last few years this assembly has seen some serious "value engineering" and as such is no longer usable in performance applications: see FA photos.
Have replaced it with the light weight Porsche unit that is capable of handling more power and torque. One of the benefits is that it weighs 6 pounds compared to the 9 pound Alfa unit and it's factory balanced (drill marks evident on the outer case). However the price is inversely proportional to it's weight.
Last edited by awesomeBLT; 07-24-2012 at 12:28 PM.
|
|
Sponsored Links
|
Advertisement
| |
|
07-22-2012, 07:55 PM
|
|
Registered User
|
|
Join Date: Mar 2007
Location: San Antonio, Texas
Posts: 1,939
|
|
And we should be careful about buying other brands. After reading about this (thank you Paul!) and then talking to Bill, I checked on another clutch manufacturer---LUK. LUK is a German oem supplier so I thought perhaps their pressure plates might stand up. I called their American office and found a tech guy who was helpful. He said the clutch discs are designed to handle 200hp which is good. However, when I asked him if the LUK pressure plates were made at the same place Sachs pressure plates he paused for a moment and then admitted that they were. So, no LUK. 
Spec lists a range of performance clutches for 105 Alfas but I didn't contact them because I found a good Sachs pressure plate from 1987 that I can use. The pressure plate failue problem apparently only exists with new Sachs pressure plates and not with old ones, many of which are still being raced even after years of service.
I'm surprised that the other vendors here and abroad apparently don't know about this problem.
__________________
Jim . . . '72 Super 1300, '70, 1750GTV, 2nd series,
'62, Lancia Flaminia Zagato3c, 2nd series
|
07-23-2012, 05:22 AM
|
 |
Registered User
|
|
Join Date: Jul 2011
Location: Munich, Germany
Posts: 2,473
|
|
|
Sachs is part of ZF group (Sachs, Lemförder, Boge, ZF) and LuK is part of Schäffler group (INA, FAG and LuK), direct competitors..........somehow doubt they use the same factory.
__________________
Dom - alfa spider 1990 S4 (BLACK!)
formally alfa 101 sprint, 2600 sprint, montreal
|
07-23-2012, 07:06 AM
|
|
Registered User
|
|
Join Date: Mar 2008
Location: Austin Texas via So. Calif.
Posts: 246
|
|
 Quote:
Originally Posted by spiderserie4
Sachs is part of ZF group (Sachs, Lemförder, Boge, ZF) and LuK is part of Schäffler group (INA, FAG and LuK), direct competitors..........somehow doubt they use the same factory.
|
Is Sachs continuing to manufacture in Germany or have they gone the way of American companies and outsourced everything to China?
|
07-23-2012, 08:30 AM
|
|
Registered User
|
|
Join Date: Jul 2011
Location: Munich, Germany
Posts: 2,473
|
|
|
depends what it days on the part! Can be made in Germany or made in Korea, afaik.
I am fairly sure their performance clutches (30% higher transmittable torque) are m.i. Germany.
__________________
Dom - alfa spider 1990 S4 (BLACK!)
formally alfa 101 sprint, 2600 sprint, montreal
|
07-23-2012, 09:00 AM
|
|
Registered User
|
|
Join Date: Mar 2007
Location: San Antonio, Texas
Posts: 1,939
|
|
Quote:
Originally Posted by spiderserie4
Sachs is part of ZF group (Sachs, Lemförder, Boge, ZF) and LuK is part of Schäffler group (INA, FAG and LuK), direct competitors..........somehow doubt they use the same factory.
|
I spoke to the Schaffler/US technical representative who was reached through their corporate phone number. He stated quite clearly that the LUK pressure plates were manufactured by the same source as the Sachs pressure plates.
The bottom line is we now have pretty tangable evidence, from a respected vendor and a knowledgable enthusiast, that there is a problem with using new stock Sachs (and possibly LUK) pressure plates in performance modified 2.0 Alfa motors.
Why don't you contact ZF/Sachs, Germany and tell us on what they say? It would be interesting to see if there's a corporate disconnect somewhere.
Is anyone using a LUK clutch in a high performance street/race 2.0 motor?
__________________
Jim . . . '72 Super 1300, '70, 1750GTV, 2nd series,
'62, Lancia Flaminia Zagato3c, 2nd series
|
07-23-2012, 04:44 PM
|
|
Registered User
|
|
Join Date: Mar 2008
Location: Austin Texas via So. Calif.
Posts: 246
|
|
Quote:
Originally Posted by spiderserie4
depends what it days on the part! Can be made in Germany or made in Korea, afaik.
I am fairly sure their performance clutches (30% higher transmittable torque) are m.i. Germany.
|
And that would be all the pressure plates they make for Porsche applications.?
b 
|
07-23-2012, 05:18 PM
|
 |
Richard Jemison
|
|
Join Date: Apr 2005
Location: Pensacola, Fl. U.S.A.
Posts: 3,213
|
|
|
Aluminum PP
I doubt the PP is any different in construction. I sure didn`t have any thing catch my eye on the one in the race car. As a matter of fact these PPs were not used on the higher powered early 911s only the touring versions ("E"). As well they were small engine cars, at the time. I suggest you do a visual design analysis 
Don`t use any type of agressive clutch material... I`m using the aluminum centered organic spring free disk.
__________________
Richard Jemison
RJR Racing
http://scuderiagiallo.com
"you don`t have to listen, but you won`t win the argument"!
"Nothing that I might suggest will be legal in California"
|
07-24-2012, 11:52 AM
|
|
Registered User
|
|
Join Date: Mar 2008
Location: Austin Texas via So. Calif.
Posts: 246
|
|
Quote:
Originally Posted by Alfar7
I doubt the PP is any different in construction. I sure didn`t have any thing catch my eye on the one in the race car. As a matter of fact these PPs were not used on the higher powered early 911s only the touring versions ("E"). As well they were small engine cars, at the time. I suggest you do a visual design analysis
Don`t use any type of agressive clutch material... I`m using the aluminum centered organic spring free disk. |
Design review:
There are 2 versions of the early Sachs Porsche PP: 911S and 911T / E. The S has higher clamping force and has a drilled out cover. These PP have "significantly" wider and thicker torque straps with clamping plates at both ends, bigger rivets and are balanced at the factory. Not to mention the metal sprayed aluminum contact plate to reduce the weight. Alfa's: none of the above.  So after you boil the ocean it comes down to: "you pay your money and you take your choice." Folks the value play here is decide how much clamping pressure you need and then buy the appropriate Sachs, Porsche PP. The Alfa units have been cost reduced to the point of being unusable and dangerous. 
BTW: Paul Spruell has both versions and some of his own reworked assemblies.
Photo#1: inside torque strap and clamping plate with large rivets (in the back ground).
Photo#2: factory balance hole
Photo#3: outside torque strap and clamping plate with large rivets
Photo#4: final assembly highlighting the nickel / iron metal sprayed aluminum center plate, sweet.
b
Last edited by awesomeBLT; 07-24-2012 at 12:31 PM.
|
07-29-2012, 01:04 PM
|
|
Senior Member
|
|
Join Date: Oct 2007
Location: Sussex, UK
Posts: 120
|
|
|
Interesting - I had a new F&S pressure plate fail in a stock 2.0 (Euro) engine about 10 years ago in exactly the same place. Put it down to a manufacturing fault. Had another one go in a similar place a few years later in a mildly modified 2.0 (c 156bhp) & replaced with an Italian C.O.M.E one which seems good. I see some suppliers offer an F&S 'Sports" version but I've not tried it - anyone else?
|
07-29-2012, 03:46 PM
|
|
Registered User
|
|
Join Date: Mar 2008
Location: Austin Texas via So. Calif.
Posts: 246
|
|
Quote:
Originally Posted by ianellisalfa
Interesting - I had a new F&S pressure plate fail in a stock 2.0 (Euro) engine about 10 years ago in exactly the same place. Put it down to a manufacturing fault. Had another one go in a similar place a few years later in a mildly modified 2.0 (c 156bhp) & replaced with an Italian C.O.M.E one which seems good. I see some suppliers offer an F&S 'Sports" version but I've not tried it - anyone else?
|
As i said I'm going with the light weight F&S Porsche units. They are 3 pounds lighter, balanced from the factory and guarenteed pretty much bullet proof. Maybe the F&S sport versions are the porsche units in disguise?
b
|
10-02-2012, 08:24 AM
|
|
Registered User
|
|
Join Date: Mar 2008
Location: Austin Texas via So. Calif.
Posts: 246
|
|
Update:
The 6# Porsche PP is installed and the car is has been back on the road for awhile.
With the lighter, factory balanced Sachs Porsche PP I have observed a couple of things. The throttle response is improved and so is the balance. I have a 67 Duetto with the stock shifter that tends to vibrate, it has been greatly reduced (almost to zero) with the new pressure plate. BTW: I had the old one balanced on the assembly at the last engine build. The durability is: so far - so good.
B
|
| Thread Tools |
|
|
| Display Modes |
 Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
|
