can g50 to replace 915

[mihalis12]

Hello. I found one g50 gearbox with low miles and I am thinking to replace mine 915. Because the g50 has deferent mount and looks like bigger, longer. Can I do that?

Can anybody to tell me if the space A = B and 1=2

Please help
thanks

[TimT]

you will have to modify the torsion tube to use that long nose g-50. Cutting the torsion tube to fit that tranny will require going to coil over suspension. If you get a earlier model g-50 you can bolt it right in place maybe you will have to do a bit of metal work to get the g-50 in (read metal work= few whacks with a hammer)

[ChrisBennet]

You need to shorten the '87-89 G50 to fit. Maybe Dean "Blown" will chime in here. He's in the process of doing that.
-Chris

[Bill Verburg]

Based on the comments from TG Fab that installed a long nose G50 6 spd its ~6" longer than a 915.

Pics and comment here,
TG Fab

[Don Plumley]

The G50 box uses a hydraulic clutch - so new pedal cluster, lines, different MC...

[dean]

In my case I have found that even with a shortened G50 the motor has to be moved back by 3/4". I think I would look into the coilover route next time.

[mihalis12]

thanks every body. I found out the solution, but I will thing if i replace mine 915.
thanks

[garrickl]

The G50 shown in the photo is one from a 89 or newer C2\C4. I have been told that it is possible to remove the "nose piece" from the C2 G50 and replace it with a G50 nose piece off 87-89 Carrera G50 ... to adapt the box to earlier 911/930. Even if this is done and even if you use an 87-89 G50 if you want to avoid cutting the torsion tube ... the bell housing and main shaft of the G50 must be shortened. If the bell housing & main shaft is shortened the proper amount the G50 will slip in without the necessity of relocating the engine mounts or cutting the torsion tube. It will be a slip in fit and the motor will retain it's original mounting points. The 87 G50 that Jimmy Privett of JP Motorsports did for me slips right in place of the factory 4 speed and the engine retains the original mounting points. The shift assembly must be replaced with an 87-89 modified G50 shifter assembly along with the 87-89 hydraulic lines and pedal assembly. This is an expensive conversion because the clutch must also be replaced ..... plan on spending over $7500 to do it right.

[RoninLB]

Originally posted by garrickl
.. plan on spending over $7500 to do it right.

is that $7,500 for parts/ not what a shop would charge

[garrickl]

$7500 is roughly what parts would cost you depending on how much you can land a G50 or G50/50 transmission for and if you want a LSD in it. Labor, depending on who installs can range from $1500 to $2500.

Parts List:

G50 1200-1500
LSD 650-1500
Machining bell housing & main shaft 1200-1700
Rebuild parts/steel synchros etc 500-1600
G50 sport clutch, T/O bearing 750-1000
G50 pedal assembly & lines 500-850
G50 shifter assembly & modified coupler 300-750

[RoninLB]

Thanks Gar.. I would buy the whole kit from Pat Motorsports, I think.. and only need a street tranny.. I hate the shifting on the 915...... Ron

[garrickl]

Buying from Patrick would insure that you get a "slip-in" fit without the necessity of cutting the torsion tube or relocating the engine mounts. Patrick will modify a G50 box you supply so if you can find one and a LSD at a reasonable price you could save considerable money and still have it done right.

[TimT]

Ron, did you ever think abouth the WEVO mods for the 915?

the WEVO gateshift, and 915 shifter could go a long way to curing the shifting ills of a 915, and be alot cheaper overall than installing a G50

[Kurt B]

Come on! You can rebuild your 915 3X at shop prices for the cost of putting a g50 in.
For cripes sake the 915 ain't that bad. For that kind of money, put the shortest shifter you can fine in there, grind the holy hell out of it, shift it with a sledgehammer if you like and just rebuild it a few times and it'll last you the life of your car.

My 915/clutch hates the heck out of me, and I've only gone through 2 clutches since 1999 and my 915 was rebuilt once in March of 2000.

[garrickl]

I went to a G50 because my 930 came with a 915 in it and the 915 just could not handle the added torque and power of a modified 3.4 turbocharged motor. There are a number of things that can be done to improve the 915 box including using 930 synchros and replacing the 2 piece bearing retainer plate with the Wevco or Guard Transmission billet piece. The G50 conversion is expensive even if you install it yourself.

[RoninLB]

Originally posted by TimT


the WEVO gateshift, and 915 shifter could go a long way to curing the shifting ills of a 915, and be alot cheaper overall than installing a G50

your right Tim, I know that.. I just want a fast shift.. this 915 only needs a double clutch act to shift like an old truck..

between the three of you guys it's obvious I gotta find a quick shifting 915 to try out.. and the tense part is that as soon as the new cams and PMO's get installed [soon] it'll be worthy of a good shifting tranny.. thanks for the reality check guys......Ron

a quick shifting 915

Is there such a thing? It does seem that after all these years, someone would have developed a solution for the 915 gremlins. That's probably the worst part of my car.

[TimT]

Mark,

look here

[5axis]

The "crash box" looks nice. Is anyone also running a ignition interupter so you could slam the up shifts. No clutch and the throttle never leaves the floor. (makes me miss my bike)

[ChrisBennet]

A freshly rebuilt 915 can be shifted fast. I discovered this one summer after I'd rebuilt my transmission. After a summer of shifting fast at track events the transmission needed to be rebuilt. Live and learn.
-Chris