I am in process of getting a custom track ready brake caliper setup on my XFR, over the stock rotors, and I have searched, I have read repair manuals, I have been to Jaguar dealerships talking to master techs, and still cannot find this one thing. The brake company needs to know what the brake master cylinder bore size. I have the piston diameters for the calipers, I just need the master bore size now. Any master techs or resourceful people in here that have a spare one that can measure it or find this info? Thank you X 3000!!!! The Dealer said any car with a 5.0L AJ133 will have the same master brake cylinder. XF, XJ, or F type.

I looked at and called around to have a kit made, even one off, and I need this info to get the new calipers matched to stock ones so they can be swapped without disrupting the stock brake balance. If we all know this info, we can go to any brake company and have calipers made for ALL the 5.0L Jags. They are all the same.

I have called,
ALCON
AP RACING
PERFORMANCE FRICTION
THE BRAKE MAN
AKEBONO
I even looked at StopTech and Brembo but didn't call them. The reason is I am looking for circuit performance for a reasonable cost of consumables, (endurance racing kind of performance) consistent and repeatable on lap 1 as lap 100. On cars as heavy as a XFR that narrows down the possible upgrades to the companies above. Basically anything with dust boots or aluminum pistons in the calipers are a no go. Has to handle heat consistently for laps and not cause any damage or burn them up.

Only one of them looks like it will be track worthy and not cost $13K and would work with me on setting up at least the right caliper. I'll be able to use any pad from any major pad manufacturer, and any fluid. I just need this bore size!

I think the rotors are PLENTY big for any brake application, @ 380mm and just need a proper caliper to finish off the brake performance. I will use these rotors cryo treated for the kit. High temp brake fluid 638 degree boiling, and stainless braded lines and brake ducts I will be happy. They will be cost effective @ $800/caliper + mounting brackets and pads. This will be epic IF I can get the master bore size....This info is NOWHERE. I don't have measuring calipers to take mine off and measure it.

 

Wow that is cheap... but am confused as to why they need the Master Cyl size when you can go from the calipers.

I've done quite a few for Saabs... as long as you are close to the stock CALIPER VOLUME on the new calipers you will be good. The single pistons (2 pistons whatever) bore is bigger and holds the same volume. (4-6 piston or whatever) calipers are available in many different final capacities. You buy the caliper to match( they have will have different sizes bores for the pistons that you just to make TOTAL equivalent volumes.

This will be easy to get or buy a caliper rebuild kit with pistons and measure buy a used master cyl and measure

I found this custom kit, twice the you are looking at. I have not done a kit from these guys, just a pre-made one I thought I would maybe try some day, but if you come up with something that would be way cool

Custom XF Big Brake Kit BBK

 

That's what I thought too, but I guess they are taking into account how much fluid is available as well to maximize the performance of the system on a track. I looked at that kit you posted and others like it like the chinese CEIKA brand (who knows they might be the same kit), Stoptech, Brembo, and others like Ksport, wilwood, BAER, and Racing Brake and the problem is they will not be much any improvement over stock when things start getting hot. I can pretty much guarantee this heavy car with all this power can get the brakes to over 1000F easily with racing pace on a big track. None of the "consumer BBK" for the street can hold up to that for any long periods. The dust boots will melt and the aluminum pistons transfer the heat directly into the fluid and boil it. The seals will get hot and start leaking and even melt the caliper causing uneven tapered pad wear.

Knowing that going into this project, It would be a waste of money to even do this upgrade unless the new setup can handle these conditions without any issues consistently and often. You can hit that target, If you know what you are looking for and not accept anything but what will work. Going with treated stock rotors will be a game changer. Even a two piece floating later will be awesome. It all starts with the right caliper setup.

 

I am also curious if anyone knows if the XFR is a Three or Four channel ABS system from the factory.

 

Odd, I had a set of willwoods on my Saab 9-5 with 13" floating hat rotors, using ATE typ200 fluid and never had issues on track days.

They sell racing versions for asphalt track. Not sure what you will be doing with a 4200 lb car to need a racing set-up, unless you are going oval track. But using a luxury sedan is kinda odd... But it wodl be awesome to see...

 

BJS - If you haven't already get yourself a copy of the 2010-2011 XFR Workshop Manual from my Dropbox here: https://www.dropbox.com/s/bet26xniua...kshop.pdf?dl=0
Then go to chapter 206-06 to read about the brakes.
Still no master cylinder bore diameter (it's a twin cylinder system) but plenty of other useful info.
Also the 380 MM front brakes are twin piston.
And the brake lines on all XFs are already braided stainless steel, it's just that they are also wrapped in rubber tubing.

 

Saab's are considerably lighter than a XFR and two, the pace the Saab can get up to is lower. The braking requirements are not linear they are exponential at very high speeds, the heavier the car the worse that exponential curve is. Taking this to the track is possible but tests the limits of brake systems to the edge, if this car didn't come with 15" brakes from the factory I probably wouldn't even bother trying this. The requirements here are at NASCAR levels, and the caliper I chose is on Winston cup NASCAR's. But my rotors are significantly bigger than theirs, so maybe it will work. Look at the chart below and see how fast the max possible speed drops off with weight. My car, full tank with me in it is around 4500lbs and that is at the limit of even a NASCAR system especially with elevated grip and horsepower that I plan on running. On big tracks like LVMS, Daytona and Sebring I had the XFR at 170+ with the STOCK power level. 2-300 hp above that will really push the limits of the system. Ferlito Racing actually raced competitively in 2010-2012 with the XFR so it is possible.



Ferlito Racing XFR

That manual is where I got the caliper piston diameters from. But it doesn't list the master brake cylinder bore...I'm going to call them again today and see if that is enough info with what I have. It doesn't look like I will figure this out soon.

 

Some years of XKRs have big brake caliper option called Alcon Performance Brake Package. Have you checked to see if it is direct bolt-on swap for you?

On my F-type, with OEM 380 floating caliper setup I never experienced brake fade on the track. I know it isn't "sexy" brake update, but consider this as a possible swap. Last but not least, F-types have optional carbon brake package.

Any of this may be a direct swap for you and likely cost less than custom-made setup.

 

I have considered the Alcon. It's a good setup. But I can't find one or part numbers. In my search a XF owner in the UK fitted a AP Racing kit with 405mm rotors. It was pretty grand. I even contacted the UK shop that built the kit. They won't ship to the US because of customs. There are chinese brands that will sell me a kit but they are no good. I dont need a whole kit. I just need a bracket on all 4 corners that fit my new calipers that are universal. I can pick any pad, fluid and use stock, or 2 pc stock sized rotors like the Racing Brake rotors. Those brackets will fit a lot of racing calipers. They are a common bolt pattern. So our options will go from one to dozens overnight. Just brackets....

The carbon ceramic f type brakes are $13K. They wont hold up to circuit abuse. XFR comes with the same brakes as a F Type right now. I faded them pretty easily stopping from 170mph+ on LVMS a few laps. My car is heavier than a F type. The stock fluid boils at 400 something degrees and the stock rotors and pads are soft.

 

I am not questioning what you are saying, for you OEM is obviously not enough. My 380 OEM setup with ducts for front holds up without any issues in the normal summer weather (~80-90F). The only thing I do to it is change fluid every year at the end of racing season. I consider F-type a heavy car, but my RWD V6 is probably lightest trim. Maybe I don't drive it hard enough? Pads do dust A LOT.

F-type carbon setup could be had used at less than $13K. Enough idiots put these cars into a wall at the end of off-ramp for the parts to be available. I don't know why you say they won't hold up, but I have little experience with such brake setup. Personally, I consider such setup cost-prohibitive due to price of replacement disks.

 

Get a used master and pull the piston and measure, problem solved

 

Hi , not sure yuo managed to sort this, but Tom Lenthall Ltd can upgrade the xfr brakes for around 3k he uses ap racing or alcon 380mm rotors 6 pots with a custom bracket for correct fitment.

 

<---I'm sure that is just the fronts...

Right now I have not seen any UK shop that will export things like BBK to the US especially now. I have already asked and they said no. I even asked for just the brackets. I have found another solution, Albeit not one that is 100% ideal. I have found the C6 Corvette ZR1 Brembo Carbon Brake Caliper set for an excellent price. These calipers have carbon rotors that are the same diameter and thickness as the XFR rotors. I have contacted a company in Russia that will make me Titanium DLC coated pistons to replace the aluminum ones. They also make Ti brake pad backing plates. There is a company called G-Loc that makes racing brake pads that can handle over 2200F+ degrees for this caliper. I also found finally a fab shop near enough to me to make the brackets to mount this setup. Its around $3k for the 4 wheel finished setup and will be completely track ready. I even found some silicone high temp seals so when the dust boots burn off the setup should live easily even on the track and not dry out or leak. Short of getting a custom AP Racing 5000R setup ($10k for 4) that is the best I can do right now.

 

I am going to ceramic coat the calipers too. The same Russian company will make me Titanium rotor hats so I can eventually just buy the carbon ceramic rotor replacement rings and have a fully Brembo Carbon brake setup with race sintered pads that makes them last longer. That will be another $6K. The difference from buying a all carbon setup now is my pistons and backing plates are Ti. Titanium has 25x less thermal transference of heat than aluminum that comes with a regular caliper piston. So with high temp DOT5.1 fluids I'm running (638F boil) it will be so much harder to fade than a regular carbon setup. Carbon Ceramic is even lower on the thermal heat transfer than Ti. Short of running a NASCAR race at 220mph+ for 500 laps I shouldn't see any fade. I don't think I would be doing that anytime soon...but don't count it out lol.

Seriously I think the tires will give out before the brakes will.

 

I was wrong again. Doing some research the C7 ZO6 and C6 ZR1 that use these brakes on track are having significant issues with their stock brakes holding up under the pressure. Aggressive rotor/pad wear, tapered pads, caliper flex, seals burning up and leaking fluid, Dust boots burning off, Boiling fluid, and more. If that is happening to a Brembo shod car that is 3200 lbs then one 4300 lb one is no bueno. Looks like there is no shortcut. Have to get AP Racing pro 5000R calipers and J hook rotors and fabricate a caliper bracket and hat kit. Sometimes there are no shortcuts.

 

Found a Paragon 410mm track setup for the XFR and a Alcon 380mm track setup as well.

Paragon 6pot XFR 410mm Track BBK setup
Alcon 6pot XFR 380mm Track BBK Setup

Pretty decent pricing for this...I am cautiously optimistic about it. I have never heard of Paragon, but they look pretty good as far as track spec brakes. Alcon are also a no brainer win at that price.

 

I have the Alcon kit, they released the lager track setups shortly thereafter. Overall great quality stage and good company to work with.

They originally made it for the XE, I am the one who worked with them on confirming the XF(X260) fitment. They also developed a set of rear (325) rear 2pc rotors with me. Working on front 350 version for those who don't want to spend for a full BBK. 2pc stock sizing is always a good upgrade.

I have this kit with me now but it didn't clear my wheels (Stock or aftermarket) so I don't have any immediate feedback for you. So if you go with this kit def reference their wheel clearance template. I need to devise some sort of spacing solution or get new wheels to make it work.

Allegedly, VAP is working on a BBK solution, saw it posted in the F-Type forum I believe.

Do you know if the x260 and x250 brakes are interchangeable?

 

I have a set of spacers that should work. H&R Hubcentric and 1"

https://trakplus.com/

Check Part 5035633 AMazon has then for $200 Let me knwo if you are interested

 

Nup, the X260 and X250 brakes are completely different front and rear.

 

Does anyone here have measuring calipers and access to a X250 XFR? Here are the measurements they need to make a 410mm x 36mm 6 pot front track kit and a 380mm x 30mm rear 4 pot. Need for front axle and rear.