Hi all:

I just found out from my transmission specialist that my BW65 is toast. We talked about swapping it for a GM transmission. I have a 1975 XJ6L with the original XK 4.2L I6 engine that I plan on keeping. Which transmission should I have it swapped to, and who's swap kit is the best?

Thanks!

 

Jaguar conversions, swaps, parts, service and advice - from John's Cars in Dallas.

 

be aware that John's conversion kit does not include a console shifter gear indicator replacement, you'll just have to make your own or guess the shift points.

I'm bored with automatics, I'm thinking a 5 or 6 speed manual.

http://classicjaguar5speeds.com/Jaguar/Transmission.htm

http://www.vintagejag.com/Parts/Tran...nversions.html

 

I thought he was the only game. Are there any another options out there (as close to turn-key as one can get)?

 

yes, if you have the big money, you can do a XJ-40 5-speed automatic transmission conversion from GWautos in the UK, but horribly expensive.

:: G. Whitehouse Autos Ltd ::

 

Thanks guys for all of the help!

 

Yeah, that conversion is actually a 4 speed auto and uses a ZF transmission which are not great transmissions to begin with, rebuilding with upgrades is expensive if you can find someone to do it. The OP could consider the 1/4 bread and use the 4 speed 700R4. The power and torque profile of the XK engine matches the typical 700R4 application and shift points would be close to ideal right off the bat. The lower 1st gear and over drive would transform the car making it crisp from a stop and docile at cruising speeds.

 

Swap the shift tower for one from an XJS. They resemble each other closely. Solves shift gate issues as well as a couple of electric issues. Back up lamp switch and neutral start switches.


Although, John isn't impressed with an OD, many have reported that it works just fine.


2.88 rear + .70 OD results in long legs.


The GM transmissions are light years ahead of that old tech but tough BW!


Carl

 

I've often wondered why John didn't recommend the OD with the 2.88 gears. I used to own a 2004 Grand Marquis with 2.73 rear gears and a .66 OD, and had no issues with performance. Considering, of course, it's an American snooze barge and not a BMW. Burnouts and stoplight drag racing were not within that car's realm of possibilities.


And the 4.6L Ford V8 makes similar horsepower numbers to Jaguars 4.2L XK 6, so it wasn't like the Ford was a powerhouse of a V8.

 

I've no idea as to the torque values of either engine and where max torque comes in.


That is the key.


Carl

 

A later BW66 from a Series 3 drops straight in.

 

With all the interest in gearbox conversions, especially to manual ones, it's surprising that someone hasn't come up with one which uses a current box which is readily available not the usual hard to get overpriced options like the Supra box or the getrag 265.
I'm getting fed up with seeing those gearboxes going for £600 to £1000 if you can find them and sky high mileages, whereas better modern gearboxes are only £150 for a good low mileage used one.
Maybe we should try a "group buy" to get the engineering work done.

 

The Tremec 5-speed and 6-speed are reasonably priced.
The shifter location is variable, too.