G50 3.2 Clutch

1972_911T · 06-13-2006, 11:07 AM

Is the OE clutch for the 3.2 using a G50 trans still rubber centred? if so what do I have to order to get a spring centred disk?

Thanks Steve

JeremyD · JeremyD's Garage

yes, still rubber centered - you want the 930 type spring centered

Wil Ferch · 06-13-2006, 12:12 PM

long story.... early 911's ( late 70's SC's) came with infamous rubber-centered clutch that explodes. Changed over to spring centered in April '83 toward end of SC production. The later 3.2's all ( at first) had spring centered...until 87 when the G50 trans came out. These use "improved" rubber-centered clutches with metal "stops" to prevent large angle twist. These were basically OK. In 1989, there was a transistion year with some old 3.2's being built alongside the early 964's which used the dual mass flywheel....which is another story altogether.

- Wil

KTL · 06-13-2006, 01:10 PM

Quote:

Originally posted by JeremyD
yes, still rubber centered - you want the 930 type spring centered

Correct. Just make sure it's the 76-77 930 3.0L disc. The later 78-89 930 cars used rubber centered discs. Still more robust than the infamous SC rubber exploder, but the spring is a better bet.

jevvy · 06-13-2006, 01:13 PM

Steve

I used to have a rubber center in my G50 box and only got a small amount of chatter - since I have changed to the LW RS flywheel , clutch and pressure plate I noticed a distinct increase in chatter.

If chatter doesnt bother you I say go light weight, if it will boil your piss then get the rubber jobby that dampens some of the noise out.

Quicksilver · 06-13-2006, 02:50 PM

Not sure about a "Lightweight RS flywheel" for a 3.2L G50. The flywheel doesn't have any of the real mass of the assembly. You aren't even supposed to resurface it.
- Wil, do you know about a lightweight flywheel for sure?

Almost all of the mass in the Carrera G50 clutch is in the pressure plate. The Kennedy aluminum pressure plate is a nice upgrade for a G50 Carrera.

I have the sprung disk in my 87 and it does rattle a bit when the clutch is engaged in neutral or you lug the engine. I don't care though. The reduced mass is nice when you are shifting.

Quicksilver · 06-13-2006, 02:52 PM

Oh, BTW...
The sprung disk costs a lot less then the rubber centered one!

Wil Ferch · 06-13-2006, 04:12 PM

I don't know of a lightweight 3.2 G50 flywheel.... not saying there isn't one, I simply don't have info on this....

- Wil

1972_911T · 06-13-2006, 04:22 PM

Jevvy was talking about a 3.6 light weight flywheel I relived him of his 3.2 last year.

So the rubber clutches from the 3.2 are not prone to exploding like the early SC ones? If so what advantage does the spring centred ones have?

Thanks Steve

Blackie911 · 06-13-2006, 06:58 PM

Just replaced my original rubber centered clutch and pp in my '87 Carrera @ 174 kkm (108,000 miles)- It still had lots of life but the pp was slipping. The rubber was perfect-- a real testament to the PO's care and the part itself. Bot another new rubber centered kit online w/ pp etc for $500... I have driven spring centered car and it sounds noisier.

KTL · 06-14-2006, 09:57 AM

The G50 and Turbo discs are still prone to failure. Just not as common as the SC units. I recall a couple of topics on this board about the G50 disc crumbling and disabling the clutch operation.

Advantage to the spring center disc is it is lighter, less prone to failure (tried and true common design) and it's easier to install the spring disc when the engine is on a stand. Rubber disc is very difficult to extract when engine is on a stand- even when using the Porsche stand yoke.

There are LW flywheels out there for the 240mm G50-type setup. I believe Spec or Fidanza makes one?

But the true place to save weight is not in the flywheel. It's the clutch housing that is the anvil. That sucker is ridiculously heavy. Patrick Motorsports and Spec sell LW clutch housings. I know there's a collection of 964 RS parts that can be used to make up a LW clutch assembly. It takes some mixing and matching of all sorts of Porsche parts from 928s, 964s, 911s, 968s,........ Here's the list.

964 102 239 31 Flywheel
964 116 011 61 Disc
964 116 028 90 Pressure plate
944 116 080 01 Bearing
950 116 813 30 Tube
964 114 143 31 Ring
931 102 111 00 Bearing
928 102 151 01 Bolt
n 014 715 3

I can't confirm/endorse that this setup works as i've never installed it and don't want to spend the $ to find out it doesn't. But I was told by someone else that it would work. I do have some experience with putting together a collection of Porsche parts to make a 964 3.6 operate with a '88 G50 car. But I can't disclose that info. or i'd have to kill you.