XJR brakes are a weak point
 

Not sure how well the Brembo's perform, but my XJR brakes are weak and i have no confidence in them. Looking for an upgrade and found Hi Spec conversions for the XJ's, anyone have other recommendations?

Talk to Sean B about Alcons :)

They shouldn't be weak in stock form, Stopping From
60-117ft, 70, 168ft, right on the dot for a performance
sedan. On the track mine exhibited 0 fade, when even GTRs
were sitting in a cloud of smoke. They don't feel sporty but the
performance is there.

The pedal feel is a bit soft on the X308's but the brakes should bite properly once they're applied hard. When I stand on my XJR's standard brakes from a high speed, they haul the car down pretty well for a big saloon.

A slightly soft brake pedal feel by design is not the same as brakes which don't work properly because there may be a fault present. Check the thick vacuum pipe to the brake servo for leaks.

Incidentally, princemarko, your other thread mentions the random engine management faults you're getting with the restricted performance mode & fault codes appearing.

Now you say that you have no confidence in your brakes-so I'm thinking that the 2 faults are related.

If you have a faulty vacuum pipe to your brake servo-or even a faulty/internally leaking brake servo-you will get poor performance from your brakes & any brake servo/connecting pipe vacuum leaks will also allow unmetered air into your engine & cause all the engine management problems you're also getting.

I think you need to check your brake servo & especially the thick connecting vacuum hose for air leaks...

I have had to hit the brakes hard a couple of times due to freeway idiots, each time I either got rear ended or came very close. In my experience a well maintained XJR will stop better than most cars on the road.