So these arrived today. 2010-2012 XF Supercharged 376mm rear rotors to match the fronts.


Just waiting for the caliper carriers. Monday.

 

Update... The rear 376mm rotors are fitted. I did find out that you need calipers and carriers from the 2010-up XJ/XF/XK Supercharged models. The 376mm rotor itself is about 10mm thicker than the 326mm unit, otherwise the mounting points are the same. These also have little vanity covers to cover the U-shaped window where you can see the brake pad.

Here are two night time photos taken around midnight after the brakes, new endlinks and rear tie rods were installed:


Will take better pics tomorrow.

 

Exexpat,

Aside from the "cool" factor of upgrading your brakes - could you outline what your objectives were and how it actually turned out? Maybe some comment on how you use the car would be useful.

Over in the XK forum I have been questioning the value of such upgrades to regular dudes/cars in terms of cost and performance. When I first got into this question the issue was breaking performance but now I'm wondering about the effects of the additional unsprung weight of the wheels, tires, massive new components, etc, etc on handling characteristics of the car.

BTW, your hard work, tech expertise and willingness to share is what makes this Forum among the best most entertaining out there.

 

This is the fifth big brake project I've done. The irony is that the times I've converted to Porsche Brembo brakes (on my Volvos) or TRD (Stoptech) brakes, the brake performance to me seems negligible. The times I've done floating caliper OEM upgrades (this case and putting Corrado brakes on my old MKII GTI), the performance improvement is quite noticeable. I don't track my cars, so I imagine there may be some other advantages to 4-6 pot calipers, but I don't feel it. Those 4-6 pot conversions have also cost me around $2k each time (fronts only). This upgrade was all bolt on, and I was able to do all 4 corners for less than $700. I consider that great value, whether you're doing it for cosmetics or performance.

That leads me why I did it now and in the other 4 cases. In my case every time I've done the 5 bbk conversions, it's been cosmetic. Performance boost is merely an unexpected bonus. The 326mm brakes looked unacceptably small to me behind 22" wheels. Now it looks right to me.

If you're entire mission in car customization is optimizing track times, I'd say you're best served getting track tires and reducing weight of the car. Aftermarket tuning programs tend to offer extremely modest results for the money spent. German magazines do a great job track testing expensive Kleemann, Abt,Oettinger, etc cars and prove this over and over again. Unless you can boost engine performance by 20% or more, usually the wheels and extra weight minimize gains.

 

Daytime photo of rear brakes

 

Nice.
Funny how such rotors still look relatively small inside you big hollow rims!

 

Hallo exexpat,

Thanks for all the information included in this post and they are very useful. May I know if the 380mm rotors will fit a 05 XJ8 L 4.2 NA with Jaguar 19" Custom wheels? I am planning to do the upgrade too.

Thanks in advance.

 

what rotors and pads did you use<?

Redstuff any good?

 

are your winter rims going to fit over these? I run 19s in the winter

 

I live in Hong Kong so there is no snow here. I am using 19" custom wheels.

 

I use redstuff pads front and rear on mine with no complaints.

And m-tec slotted rotors which again are holding up well

 

I have the 365mm brembo setup on my X350 do you think I would see much improvement if I did the same convention. If it would fit?

 

I had the Brembos on my old X350 and the 380mm brakes on my X351, and to be honest, I preferred the pedal feel of the Brembos. Different cars and all so take it for what its worth.

 

Can't really comment on the direct difference between the brembo and the XFR spec as I haven't driven both types.

​​​​The rear hubs are different on the brembo car though (seperate handbrake caliper) so the backs won't be a bolt on like the later models with the integrated handbrake mechanism. Not sure about the spacing of bolts on front hub comparing x350 to x358 either although I am pretty sure you can fit front brembos to any of the models indicating they are more than likely the same.

 

Has anyone measured all the caliper piston sizes for these alternative calipers? I'd like to see the math if brake balance is drastically different compared with stock.

 

Don't know about the 'math' but would suggest front calipers there or there abouts same as a four pot brembo ( two large pistons vs four smaller ones on the brembos).

Rears are the same as stock so far as I can see.

Car has never tried to swap ends on me and I have had this conversion on for years, balance will be the same as an XFR as similar weight balance etc.

 

Double post

 

The bolt spacing of the Brembo calipers is different to the ATE ones.

The front vertical link of the 2003-2005 XJR and STR was a different part number, the casting itself was different, the spacing of the caliper mounting lugs is different.