Late 6.0 Coupe converting to Manual Box??

[Jaguar5993]

Hi,
Hoping to take early retirement next year and not buying a new car and I'm going to get my 1995 6.0 Coupe how I want it,after owning it for 18 years and everything is DIY.
I already have the AJ6 Engineering full performance kit on it, but together,later with other engine mods (hoping for 370-420 bhp max- H.E heads!), rads, brakes,suspension and body restore etc.

Looking to hear from other 6.0 owners who have converted their cars to a manual box.

I totally get it will change the car and might be worth doing if you have a 5.3 V12 and prefer to get away from the GM TH400 3-speed box and there is a lot of info out there.
I like what the guys do at Simplyperformance, but not too sure if it is worth doing for the late 6.0's, as my auto has the better GM4L80-E 4-speed one.
Would there be too much rear wheel spin?(although it will be in top form at the rear).
I guess I just don't want to regret it and waste money.
Any thoughts please.
Kind Regards

[BigCatXJS]

Unless you have desire for 6 speed manual transmission (see link below - looks fun!) I personally would keep as a 4-speed auto;

https://youtu.be/y7F9U8GHPd4

I heard (hearsay) that its necessary to downgrade some 6.0 ignition/circuitry down to 5.3 spec to support running manual transmission. I'm not sure how accurate that is or exactly why, or whether the Omex / Emerald ECUs make this a moot point.

[Jaguar5993]

Hi,
Thanks for a reply.
Yes...great video...It was that YouTube post that got me thinking about applying a manual box to my late 6.0 Coupe.
I have heard that the Driven Man boxes had some issues, some incorrect parts turning up and the cost, maybe?
I would still favour the 5 speed Getrag.
I think also, there might be a need for max rubber under the standard wheel arches, looking at that clip (that's another subject and post).

With the electrics...nothing surprises me with these late cars, but I haven't heard anything connected with changing to a manual.
I still think any manual box is just going to use that V12 power curve better ,whether the 6.0 has to be de-tuned a bit or not (probably just an AJ6 Engineering ECU mod etc.)
I guess I can get all my answers I might need, with those guys at SimplyPerformance.
Its a future project, so plenty of time to work it all out.
Kind regards

[BigCatXJS]

I would completely agree that manual transmission unlocks a lot of potential. I have a 5 speed getrag from a donor 3.6 that had died. Amongst many other mods it has transformed the car. My use-case was compelling as my XJ-S had the GM 3 speed transmission - very strong and reliable but so limiting and inefficient.

I recently was invited to a corporate track day at Donington. I should have taken the BMW E92 coupe but instead the XJ-S came with me. Well, she was still a handful (too much weight) but a number of folks were surprised to see the cat hit 110mph+ on the paddock straight. Slow by modern standards - the Alfa 4c in our group hit 130mph with me a as a passenger. My XJ-S is 30 years old so not bad for an old timer