G-50-01 through -05 transmission interchangeability experts please.

[MotoSook]

I want to mate a 964 G-50 to a 3.2 DME controlled engine without modifying the bell housing or input shaft.

According to the part numbers, the 1989 964 G50-02 pressure plate is the same as the 87-89 3.2 Carrera G50-01, -02 pressure plate, both part number 950-116-023-03. The 1989 3.6 flywheel has a different part number than the 89 3.2 flywheel, so I conclude that I cannot use a 964 flywheel with a 3.2 DME reference sensors. If I am able to source a 1989 G50-02 from a 964, I should be good to go, right? (Did the G50-02 used in the 964 have that later single point nose mount?)

Between 1990 and 1991, the G-50-03 showed up and the pressure plate for it is a different part number, 964-119-028-90. This same pressure plate is also used in the G50-04 and -05.

Pelican lists a Sport/Race pressure plate from SACHS for all 964/993. So does this mean that all G50 pressure plates are dimensionally similar and I can interchange G-50—01, 02, -03, -03 and -05?

If that is the case, I can bolt any of the 964 G-50 to a 3.2 DME engine using a 3.2 flywheel, G-50-02 pressure plate and a 930 spring center clutch plate.

Can someone confirm or steer me down the right path?

I assume I will then have to use a 964 starter?

I'm not worred about the transmission mounting as I will modify the mounting to work on my tub.

[KTL]

There's no '89 964 G50.02. The '89 964 was only 4wd with the G64.00 transmission.
A G50.02 was used with 3.2L '87-'89 Carrera. The 1990 964 was the first year for the 2wd model & G50.03

The My understanding is the '89 964 flywheel is the single mass flywheel used with the early G50 style clutch. So that would mean it's similar to the 87-89 3.2 flywheel in dimension, but if i'm not mistaken the 964 crank flange is different and that's what prompted the slight change to the flywheel. Otherwise I suspect Porsche could have used the 87-89 flywheel in the '89 964

The change in pressure plate for the G50.03 was prompted by the use of the dreaded dual mass flywheel. So all G50 pressure plates are not dimensionally similar.

[Dan J]

use the 3.2 flywheel,clutch,pressure plate it will all line up.

I have a complete 3.2 G50 stack and a 964 lightweight stack on the bench putting a straight edge across the t.o. ears they're level

The cranks are the same The 964 flywheel has a different number of teeth and they're farther from the case

[MotoSook]

Great info!

You wouldn't happen to have a G50-03 to -05 there to check the pilot bearing ID or splines using the 3.2 flywheel?

use the 3.2 flywheel,clutch,pressure plate it will all line up.



I have a complete 3.2 G50 stack and a 964 lightweight stack on the bench putting a straight edge across the t.o. ears they're level



The cranks are the same The 964 flywheel has a different number of teeth and they're farther from the case

[Blackbyrd]

What are you trying to put this into ? just need a G50-01 nose cone to fit a G50-03/05 if it's a G50 car already.

It's better to use a G50-03 than the late G50-05 on earlier cars

[MotoSook]

Originally Posted by Blackbyrd

What are you trying to put this into ? just need a G50-01 nose cone to fit a G50-03/05 if it's a G50 car already.

It's better to use a G50-03 than the late G50-05 on earlier cars

This is for a caged race chassis. No issues with torsion bar tube interference. The nose cover will be dealt with.

[Dan J]

Pilot bearing and splines are the same

[MotoSook]

Originally Posted by Dan J

Pilot bearing and splines are the same

Great! Thank you, Dan.


With the above information, I assume all G50 bell housing are the same, so if I use a 3.2 FW, PP and ring gear, I should be able to use a 3.2 starter. Right? (Dan or anyone?)

[Dan J]

use the 3.2 starter

[MotoSook]

Thank you, Dan.

Do you know the G50 output/drive flange bolt size and diameter? Are they the same from G-50-01 to -05?

[KTL]

The bolt in the middle of the drive flange that bolts it to the diff is M10x85, all same part number for G50s thru .05

The CV bolts are M10x50 for all G50s thru .05

[MotoSook]

Thanks Kevin.

So from the collected info, and what I found in this thread

CV Joint and Axle/Half Shaft Compatibility

I should be able to make it work with 108 mm axles from a pre-968 car,

From the above linked thread:

[KTL]

Yep, with the g50 installation the axle solution is simply a matter of installing the 86-89 Carrera axles (with their larger self-locking outer stub axle nut and thick spacer/washer) and the associated M10 CV bolts on the trans output flange.

No outside the box thinking necessary unless you want to figure out how to eliminate the one-piece outer CV joint/stub axle assembly. Challenges there are you can use 930 or early CV but you need custom axle length (Sway A Way et al can provide these) and will need to modify an early 74-older outboard stub axle flange to accept the two additional CV bolts (early stub axle has 4 bolts + 2 roll pins). That gets expensive in a hurry with custom axles

Just easier to drop in a new Carrera axle that's been filled w/high quality grease, not that GKN economy grease. Only downside is that friction-welded one piece outer CV. Not a big deal though. Pretty durable axles off the shelf when you regrease them right from the get-go.