G50 clutch replacement experiences?

[Simonk]

Specifically '87-'89 3.2 Carrera. I've had my rubber centred clutch plate replaced with a spring centred one and the noise from the gearbox is terrible. Gearbox chatter and rattle in every gear throughout the rev range when the engine is under any level of load. I've read about similar cases and it's been solved by installing the Porsche rubber centred clutch plate. Peter Zimmerman has noted most G50 cars experience the same issue. The whole point of the rubber centred plate was to dampen the noise from the G50 which is inherently noisy. Problem is, Porsche Australia are no longer supplying them and only have the spring centred ones available. A quick look on Pelican confirms they too are only selling the spring centred ones. Design 911 UK do have the rubber ones listed so the option is there but I'd like to know if anyone else has experienced this and if so, did you do anything about it?

[Buchanan Automotive]

Its actually a engine firing impulse noise that the transmission simply transmits to the human ear , hence why Porsche installed the dual mass flywheel to all the manual transmission with less than 8 cylinders beginning with the 964 & then the 968 , when this technology became available , a dual mass flywheel very effectively dampens out the firing impulses , hence why the 964 ,968 ,  993 , Boxster , 996 that were just road cars had them , it makes a massive difference 

Note } Firing impulse noise ( with no dual mass flywheel ) from manual transmissions gets worse with less engine cylinders ( but large pistons ) , meaning a 3.0L 4 cylinder engine has a big potential to cause these noises at low RPM , a 3.0L  6 cylinder engine slightly less , a 3.0 L   8 cylinder engine even less & 3.0 L   12 cylinder engine even less still & a  3.0L   16 cylinder engine way way less still , its just basic physics

The early rubber entered clutch plate ( be it 911SC , 911 3.2 , 944 2.5 NA , 944S , 944S2 3.0L ( not 951 or 911 turbo ) were in a way the early forerunner to the dual mass flywheel ( manual trans only ) , this was to make the car more user friendly( quiet ) & more like a current to that era Japanese car , meaning as quite as possible in the driveline 

When the 3.2 911( G50 ) came out in 1987 , customers who purchased them( leased mainly ) complained about the very noise that you are referring to ( BUT ) with a rubber entered clutch , could you imagine the complaints if their 911 ( 1987 - 1989 ) came from Porsche with a spiring centred clutch plate ( OH my GOD , the sky would of caved in )  , how do I know ? , I was working at a large Porsche dealership from 1977 to 1994  and it was quite interesting to see how many people ( who leased these cars ) complained about a noise that could not be rectified , but made a whole lot worse once the rubber entered clutch plate was discontinued .

Why was it discontinued ?

Answer = because if you drive the car a little bit aggressively or badly( poor driving style )  , the rubber entered clutch section would just break & hence why it was discontinued

If you can still buy a new ( old stock ) rubber entered clutch plate , and you are that concerned , then you have no choice , you have to buy it and install it , but remember if you can buy one its already quite old & its rubber 

Regards

Bruce Buchanan
Buchanan Automotive  

[Simonk]

Thanks for your extensive reply Bruce. This really isn't good news for early G50 owners. Perhaps mine's a particularly loud example but I don't know anyone who'd be happy to put up with it. If it was a nice mechanical sound then fine, but mine sounds like it's broken. 

Would you know when they discontinued the rubber centered clutch? I'm interested to know how long NOS would have been sitting on the shelf. You're right in that if it's been sitting around for 10 years, I probably don't want to put it in my car.

[Buchanan Automotive]

I really do not know when it was discontinued , you could email the supplier in the UK ( new old stock ) and see if they know if there is a production date on the box the clutch plate comes in , even a date from a Porsche dealer on the "possible last date sold " is only a guide because the actual production date could easily be 10 years before that

I know we stopped buying the rubber centered clutch plate for these at least 24 to 25 years ago ( maybe more ) 

[Philbee]

Wow... I’ve never heard about this and my car is an ‘87 3.2 chassis,  g50 box. I have no such sound luckily. Is this my destiny? 

[Simonk]

9 hours ago, Philbee said:

Wow... I’ve never heard about this and my car is an ‘87 3.2 chassis,  g50 box. I have no such sound luckily. Is this my destiny? 

I honestly dont know Phil. My car sounds like a piece of shit so I find it hard to believe they all sound like mine with a spring centre clutch. Otherwise this issue would be as famous as the IMS. I will eventually source a rubber centred one from the UK.

[Philbee]

Yeah it would be a big 3.2 long standing issue to your point above, ... So hate to say this.... maybe there’s something else going on in the box or connecting to it..? 😢

[Peter M]

Just had a new plate installed in my G50 3.2 with a similar increase in gearbox noise to what you are experiencing Simon.

 

[firstone]

I've had a broken spring in a clutch plate make horrible noise but not effect it's operation.