Can you replace a 915 trans with a g50 easily

srstevenso · srstevenso's Garage

Hi:

I've got an 81 911 SC Targa that I love. My 915 tranny works pretty well but have often thought of replacing it with a G50 since they get so much praise.

Can they be swapped or is it a major modification to add the G50 in place of the current 915?

Thanks for the help!

Peace,

Scott

oh snap · oh snap's Garage

It is a major modification. The torsion bar tube for a 915 car doesn't give enough room for the g50. Unless you are going for big power its not really "necessary" anyway, refresh and tweak you 915 a little and it can be almost as good as a g50, and you'll have a weight advantage.

Joe Bob · Joe Bob's Garage

Big job as noted above. I modded my 915 with EVO upgrades for my 3.6.

timchar · timchar's Garage

It's also a hydraulic clutch and many major changes. Try starting with a new shift coupler, made a big difference for me. Check with the coupler whisperer, ed/ivangene. Tim

srstevenso · srstevenso's Garage

Thanks to all for the help. the 915 is working well but the thoughts of a G50 (rock cruncher) isn't unappealling! Looks like the original will remain in place.

Peace,

Scott

DUK · 01-28-2012, 04:53 PM

You can always get a G50 shortened to fit. I think it only costs about 12k.

JEM911 · 01-29-2012, 01:46 AM

Talk with Patrick Motorsports in Phoenix, AZ, if you want to look at a shortened G50.

chris_seven · 01-29-2012, 02:23 AM

Roger Brown at California Motorsport shortened one for us a couple of years ago and it has worked well.

You will also need to change the flywheel, clutch and look at starter position.

The gear lver rod and console will need to be changed as the 'gate' on the G50 is in the box and if you leave the 915 tower in place the external springs will fight the internal gate.

I am niot convinced the 915 will ever shift as well as the G50 even with a lightened second gear and all the other mods.

The ultimate solution must be to develop and fit a 'dog rings' in place of the synchromesh.

arbita1 · arbita1's Garage

I rebuilt a 915 a few years ago. (There's threads on it here.). That combined with seine systems gate shifter feels amazing. I was always disappointed with my 915 after driving a g50. Not anymore!

Dave Colangelo · Dave Colangelo's Garage

As stated above a 915 in good shape is as good as a G50. If it does not bother you to the point where it is unbearable its not worth changing in my opinion. For that matter if you are that serious abut it you may want to consider selling your car for a G50 car. They are a bit more but you will most likely spend that making all the upgrades any ways.

Regards
Dave