Jasko

OK - I know this was just discussed , but just a bit more info please.

Has anyone placed a LWF, pressure plate, RS clutch in a 89 bellhousing? I know that the 89 has the "89 LWF", but I want to use the lighter pressure plate and the 996 RS clutch disc - this is a track car only.

I know that KirkF has a LWF/ RS clutch in an 89C4, BUT he had the post 90 bellhousing/ starter, etc.
From what I am gathering on other threads, the LWF/ RS set-up will not mesh with the starter on the 89 bellhousing because the pressure plate/ flywheel assembly is shorter front to back, and the starter gear ring is located differently. And updating to the 90- starter (longer nose) is not possible without changing to a 90- bellhousing as well. It seems that it would not be possible to fit the 89 bellhousing with the LWF/RS setup because of the starter mismatch - anyone with direct experience on this?

Or would it be possible to mount the 89 starter ring gear on the front of the 90- pressure plate in order to engage the starter?


Thanks,
Dave
89 C4

KirkF

I don't have any answers but I can add a couple things:

1. The starter ring on the dmf flywheel is on the engine side of the flywheel, the starter ring on the 89 is on the pressure plate side. That is why there is a long nose and a short nose starter.

2. I think the starters might fit regardless of what transmission you have. But i didnt have an 89 starter to test it with.

I had heard something about requiring a different bracket for the flywheel sensor between the '89s and the later lwf/dmf.

So you may only need to change your starter and that bracket.

I have heard that you cannot fit a DMF flywheel in the 89 bellhousing. ( I am guessing because it will rub on the inside edge of the bellhousing. It is deep compared to an 89 flywheel) But that shouldnt be a problem with a LWF.

If you want to pursue this, I would model the setup and do a set of drawings.

You would have to draw the components, measure their dimensions and then see how they fit together. (Most importantly the bellhousing)

The other option is to buy all the pieces and then try and assemble it and see how it works. ($$$)

If you want to model it I will be happy to take what measurements I can of the parts I have.

Kirk

Jasko

KirkF - thanks. I may take you up on the offer to measure the depth of the flywheel/ pressure plate assembly for both, as well as the individual components. I assumed that the DMF pressure plate was thinner than the 89pressure plate, and the DMF itself was thicker. Is the guide tube longer or shorter.

I was looking at part numbers this AM - The 89 clutch assembly seems to match up with the 87-89 Carerra parts number - ie, pressure plate, rubber clutch disc, flywheel. Probably left overs -

There was a aftermarket light weight pressure plate made for the 87-89 Carerra (EBSracing has one - will post part # later) that might fit the 89C4 bellhousing/ starter setup. At least the writeup says that it will fit the 89C4 -hmmm. It weighs 13# so not as light as the RS pressure plate (11# - 4700gm) , but better that the 89C4 (at 22# - 10050gm). That may be an alternative instead of going with an RS setup - ie 89 flywheel, and lightweight 87-89 Carerra pressure plate - I wonder if the 996 clutch disc would fit. I'll post this on the 911 Carerra side to see if anyone has experience with the lightweight setup.

Thanks,
Dave 89C4

By the way Kirk - my connecting rods were 930 parts as well.

KirkF

Sounds like a good plan, keep us updated!
If you need measurements I am only home on weekends (I work out of town).

Kirk

Red rooster

Dave ,
I had a look at the clutch cross section drawings and the G50 3.2 /964-89 look like the same thing other than the flywheel DME crank sensor ring .
The 964-89 starter looks like a heavy duty 3.2 and the guide tube area looks identical .
With this light weight plate its amazing that so much weight can be lost.

The 964 clamp force is 8800-9600 N and the 3.2 G50 is 7800 -8600 N.
Might be worth checking the clamp force on the lightweight plate .
Be interesting to see what you come up with as a rubber centre clutch plate alternative . The 996 plate is an interesting idea.What promted that other than ,I guess, it fits !

All the best

Geoff

Jasko

Geoff,
Thanks for checking on the sizes. That confirms what I was hoping to find. The part number for the 87-89 carerra pressure plate and the 89 C4 pressure plate is 950-116-023-03 if I'm reading this right.
Just got off the phone with Kennedy Engineered Products http://www.kennedyeng.com/porsc_pp.htm

Their G50 pressure plate will fit the 89C4 bellhousing. They have 2 stages - Stage 1 will clamp to 536ft lb with stock clutch, and stage 2 will clamp to 630ft lb with stock disc. They start 30% increase over stock pressure plate. For the horsepower requirements for the C4, the Stage 1 should be sufficient. The KEP pressure plate in 13lb and made with Billeted Aluminum. Sells for around $650 without throwout bearing.

As for clutch disc - the 87-98 carerra can use the spring loaded disc 930-116-014-02, so I am assuming that that will work in the 89 C4 setup as well.

As for the 996-116-015-30 clutch disc , a local race shop uses those on all its RSR, Cup Car setups - I think that its used even on the modern Cups as well. They actually use the solid, 4 pad pucks.

Dave
89 C4

Red rooster

Dave,
That clutch plate is for a very early 4 speed turbo.Be interesting to see how it goes.

Good luck

Geoff

Jasko

Geoff - But its also listed for the 87-89 G50 transmission - here...
http://www.pelicanparts.com/catalog/...Tclutc_pg2.htm

It seems that the 87-89 G50 Carrera could have either the rubber clutch or the spring clutch plate.

Dave
89 C4

Red rooster

Dave,
Well spotted ! I am really interested to see how the end result goes.Stuff like drive line rattle .Keep posting as you get there .

Good luck

Geoff