Black Box

I have asked this question on another forum and not got any detail why it will or won't work. I have a modified base boxster that has been tested with as much HP as a 03 S 3.2. I would like to install a 6spd S transmission in the car.
1. Will it fit?
2. Beside the clutch PP and Fly wheel. What else would I have to replace?
3. Has anyone done this on a 2.7

kcpaz

Clutch disc is different but the pressure plate is "technically" the same.

The biggest difference is the axles and rear suspension uprights. Also, depending on your exhaust configuration, you may have to change the mount on the transaxle.

eric523

Yep, you can do it. I'm in the process of doing the same in my car now.
I'm not done yet but I've already purchased Boxster S axles, Boxster S rear uprights/hubs, new wheel bearings for the hubs, and new rear brake rotors. I'm not sure if I'll run into a few other little things yet.

Rick DeMan

Here is a short list of the things needed,

1) Complete clutch assembly.. flywheel is the same.
2) Mount brackets that attach to the trans case
3) rear suspension uprights complete with bearings
4) both axles
5) Shifter cables and brackets on trans
6) Muffler brackets if you run the factory style exhaust
7) Clutch slave cylinder and Line that runs to the middle of the car.

Thats pretty much all it takes...

insite

anyone know if it's possible to swap out the transmission flanges w/ the 5-speed & use the original axles?

txhokie4life

I have an S I am parting out that has all that.

Everything in good condition all though the CV Axles boots need to be rebuilt.

PM or email mike@lonestarrpm.com if interested.

mike

DOUGLAP1

Just a couple of negatives to point out:

1- The 6 speed gearing is quite tall. Mine does something like 74 mph in 2nd gear. For the street it is fine, but I really give up some low end torque on an autocross course.

2- The 6 speed is dimensionally longer from the motor flange back to the drive axle centerline. I noticed this when changing out my clutch, as the axles are always at an angle toward the front of the car. Apparently Porsche just bolted in the 6-speed, and figured that the CV joints would take up the difference. This is why the 986S is much harder on CV joints.

eric523

And a positive point to those, is the 6-speed box has aftermarket support with ring and pinion options as well as a shorter 3-6 gear set available. I have the short 3-6 gears, but the R&P would likely be better for AX. There is also better diff options in the 6-speed. You can also get steel synchs, and oiling upgrades. All are $ though...

Black Box

Running out the gears in Third, Fourth, and Fifth, what are your speeds say at 6800 to 7000 RPM.

eric523

you can see the gear charts for the 5 speed, 6 speed, and other 6 speed aftermarket options on this page.
http://www.californiamotorsports.net/986%20Boxster.htm

jittsl

I'm sure Eric could tell us more precisely but I believe the 6 speed weighs an extra 30+ lbs in a bad place. Just something to think about.

eric523

Yes, the 5 speed is approx. 110lbs, 6 speed is approx. 140lbs. Add a few more with an LSD.