Looks like I’m in need of a transmission rebuild. Many issues.
I figured while it’s out why not make it better. I’ve always thought of it as a slush box. 03 XK8 BTW.
To me sport mode should be just that. Shift when I want and quick. I’ve been a hot rodder my whole life. Chevy guy.
I know where to go and what to buy for them. But Jaguar, I’m lost. Thanks.

 

As far as changing the shift profile, you are basically out of luck short of finding someone who can modify the software. This isn't like the old days where you could drill out holes and change check valve springs and have a "shift kit". There are no mechanical accumulators to modify even, instead there are variable flow valves that are software controlled.

Even if you try to change pressures and flow restrictors, the control software will learn around these modifications and you will end up back in the same place as today. Jaguar wanted it to be slow and soft and unfortunately we are pretty much stuck with their choice.

You can do things for reliability through, even billet shafts and clutches and all that. Search for the 6R80 Ford transmission, basically a 6HP26 built under license from ZF. Lots of those parts interchange and the mustang crowd has found all manner of ways to creatively break stuff and replace it with expensive billet something or other.