SNEAK PEAK:

XK8 LS1- 6 Speed ( Manual Transmission ) Project Update,  January, 2014

When the new XK8 was introduced in 1997, the car caused quite a stir, and included many design elements reminiscent of the XKE of the 60's and 70's. However, one key element of that sporty heritage was missing- a manual transmission. And in the years since that introduction, Jaguar has never addressed that desire of XK8 (or XKR) owners to shift for themselves.

Building on the successful XK8-LS1 (automatic transmission) conversion kits we introduced approximately 2 years ago, and with plenty of encouragement from customers, we went back in to see if indeed a manual transmission in these cars was possible. Because the (T56) 6 speed manual transmission is much slimmer than the 4L60E automatic transmission (around which the original XK8-LSx kit was designed) there likely would be enough room in the  transmission tunnel. However, there were 2 key areas concern that were definitely not a slam dunk:

1) Pedals- How to re-engineer the XK8 brake pedal box to also accommodate a clutch pedal and hydraulic master cylinder. Unlike earlier XJS and XJ6 models that used a cast aluminum pedal box that could be modified/welded for a clutch pedal and clutch master mount, the XK8 uses an injection molded plastic pedal box that cannot be altered that way.

2) Shifter- Would the T56 shifter come up in a location even close to the original automatic shifter position. And if not, could anything reasonably simple and inexpensive be done to make it so.

The only way to find out for sure was to get in and do it. A 97 XK8 parts car was used as a testbed, and a junk LS block, heads, and spare T56 transmission were put together as a dummy drivetrain. Besides the transmission mount, the plan was to use all of the same components as the XK8 automatic kit and that  worked perfectly. The dummy drivetrain slipped right into the car, and the only real work was to verify the shifter position, and then open an appropriate hole in the tunnel for the shifter itself. Cutting to the chase, the proper combination of some OE GM T56 shifter components and a little tweaking worked perfectly. Here's a pic of the shifter in the prototype, with the (for the most part stock) console around it. All that has been changed is the addition of a black leather boot to replace the original J-gate shifter base.

The pedals portion of the project was quite a bit more involved. The objective was to have a finished product that had a factory appearance and feel, but could be incorporated into the car with no firewall modifications and little, if any, changes to the original XK8 pedal box/pedal/booster/master assembly. After all, this project was to ultimately become a kit for customers to install on their own cars, so requiring sheetmetal modifications to the firewall would be outside the "friendly conversion package" goal. After much work, several prototypes, and  many tests, a final version of the pedal assembly was devised that met all of the requirements. The new clutch and brake pedal assembly fits nicely into the footwell with adequate spacing (for at least my 10-1/2W feet), uses a common off-the-shelf clutch master cylinder, and it is even possible to install the entire new assembly without having to remove the brake master cylinder from the car (so no brake bleeding is required- very nice). Below are some pics of the new pedals in the footwell and a topside view of the installation with the new clutch master . The clutch master is the silver unit sticking up vertically behind the brake booster with the blue hose leading to the remote reservoir, mounted inboard. You can also just see the braided steel high pressure clutch hydraulic line. Everything fits nicely under the plastic cowl cover and the hood closes normally.

After the successful fit of the dummy drivetrain, an actual running 2002 Camaro Z28 LS1-6speed car was purchased as a donor.  Below are some pics of the donor car (yes, we took apart a good running Z28, but it wasn't that nice a car, so no great loss)

And this nice low miles 1998 XK8 will be converted (great body and paint, very nice interior and top, 18" wheels, etc).

The new drivetrain was prepped  for the conversion and dropped into the car. Just like on the test chassis, everything fit nicely. One important test was to connect the clutch pedal hydraulics to the transmission and verify that pedal movement actually releases the clutch itself, and it does. Now it was just a matter of going through the basics of the conversion to get the car running (wiring, plumbing, exhaust, driveline, etc.,.)  just like on an automatic install.

As of this writing, we are 90% finished with the installation and almost ready to fire the engine. Stay in touch with us for updates on this car.

Kits will be available soon!!   If you're interested in a conversion like this for your own XK8 or XKR, please get in touch for more info.