915 Box On A 3.2

[1972_911T]

To mount a 915 gearbox onto a 3.2 that had previously had a G50 box do I need to change the flywheel and clutch or can I just get away with changing the clutch if the flywheel is in good condition?

[Bill Verburg]

You need a clutch and flywheel that match the transmission, G50 parts do not match 915 trans

[1972_911T]

Ok thanks!

Is it also true to fit a G50 box in an early car you need to do away with part of the beam and put coil overs on?

Steve

[Joeaksa]

No on the coil overs, and no idea on the beam. The later model Carerra's had different type's of torsion bars in the rears (I believe) from the earlier years but no need that I have heard of to run coil overs.

There were changes in the body with the G50 but believe that it would not be an issue to switch a 915 back in the car.

JoeA

[jtf914]

You will also need shorter mounting studs since the G50 case is thicker than the 915 case.

[IROC]

Originally posted by jtf914
You will also need shorter mounting studs since the G50 case is thicker than the 915 case.

Very good point.

You essentially need a clutch and flywheel for an '84-'86 911. Don't forget the ring gear also, it isn't an integral part of the flywheel and must be ordered separately.

If I'm not mistaken (don't quote me on this), you'll also need shorter bolts to install the pressure plate onto the flywheel. My '88 3.2 came with the G50 flywheel and clutch assembly and when I went to install the 915-compatible stuff onto it the bolts that were used to mount the G50 pressure plate were too long for the 915 pressure plate. Maybe someone else will chime in as it's been years since I did this...

Mike

[ChrisBennet]

Originally posted by 1972_911T
Ok thanks!

Is it also true to fit a G50 box in an early car you need to do away with part of the beam and put coil overs on?

Steve

The G50 is larger than a 915 and you either need to replace the torsion bar carriers with one from a G50 car or cut the old one (to make room) and use coil overs to fit a G50 in a pre-G50 car.
-Chris

[MotoSook]

Yep...you'll need the 84-86 clutch pressure plate, clutch dish, flywheel, pilot bearing, pressure plate bolts. You'll also have to notch the bellhousing to clear the reference sensors.

The G50 is wider than the 915 (unless it's a 915 from 84-86), so if you are going to put one in a non-G50 car, you'll have to cut the t-bar tubes to allow the G50 to fit. That's why they moved the t-bars outward on the G50 cars. That's probably why you asked about the coil-overs.

How about telling us what you are trying to do (car? have you selected a tranny?)

Edit: Chris beat me to it, but I also wanted to add that I will have a new (slightly lighten) 915/3.2 flywheel for sale. We are using something else, so a new, never run flywheel is available. E-mail me if you are interested)

[1972_911T]

The car is a 72 and hopefully ill be using my 72 915 tranny however this does need some overhualing due to whining im thinking the input shaft bearings, so thought as the eninge im looking to buy is coming with a G50 clutch and flywheel it may just be easier to use that but now im thinking maybe not!

To top this engine off im also hopeing to use megasquirt and spark instead of the Bosch ECU as there prone to failure now been nearly 20 years old and replacements are harder and harder to find!

Any one know of a good book for overhauling 915 trannies?

Steve

[Porsche Doc]

Here is a pic of the knoch in the torque tube to install a G50 in an older chassis.

[jpnovak]

Don't forget to notch the bell housing for the crank angle sensor on the 3.2. If you get rid of the Bosch ECU what will you use for spark control? Are you doing a MS&S installation? YOu will still need some type of trigger since the 3.2 dist does not have one.

[1972_911T]

Yeah im wanting to use MSnS I have been looking into if the original 3.2 crank sensor on the flywheel could be used failing this I will just use the normal 36-1 wheel on the pully side probably from the ford EDIS setup!

[1972_911T]

Just noticed what you said about the 3.2 Dizzy this will be going completly and be replaced with the EDIS 6 Setup as this dosent require a distributor.