I have a 2007 Jag XK coupe and I'd like to upgrade to high performance brakes and calipers etc... Does anyone have or know of any recommendations? Thank you in advance, Chris.

 

I'm running the same car, and as those that know me can attest, I'm a very aggressive driver on back roads.
To be perfectly honest, the Jags brakes are pretty good overall for anything you will encounter on the street. Track use may press them, but not by much if you have the right combination. Those that track their Jag may provide deeper input there.

I upgraded all 4 rotors to StopTech slotteds, with the fronts cryoed.

I dumped the OEM pads in favor of custom made Porterfield R4-S. I wanted the original R4 compound, but let the salesman talk me into the newer S version...grrrr...mistake). The R4-S failed to provide the power I was expecting and they squealed like a banshie!
I pulled them quickly and swapped to EBC Yellow Stuff, which I run currently. The Yellow stuff are actually pretty nice pads, but the peddle feel is still a little vague and they don't have a great initial bite. I suspect I'll call Porterfield and get that set of R4s like I first wanted (which, by the way dust like a son-of-a-gun).
My concern is braking power, and not looks, so dust is just a by-product of having great brakes.

Before spending cash on a big brake upgrade, consider a decent set of performance pads and invest in good high performance tires. I think the Jag will impress you.

Remember > Brakes stop tires.... Tires stop cars....


My 2 cents
Vince

 

A decent "high carbon" rotor in stock sizes (like Centric, Stoptech, R1 Concepts) with a ceramic pad (e.g. EBC Redstuff) will be more than sufficient for a street car.

Do the X150's have braided brake lines from the factory? I think they would (the X350 XJ has)

 

I do not recall them being braided, but then, most brake lines these days are internally braided Kevlar so they are extremely strong and make ballooning a thing of the past.

Ceramic pads typically have a lower friction coefficient than even OEM pads, so for stopping power they really don't rate in the Improvement department unless dust is your only concern.

I used Red Stuff once on my Lexus, and they failed to hold up at a single track event. I quickly swapped them off for a set of Hawk HPS, and the difference was night and day.

 

There is a big selection of race performance pads, but usually the higher the friction coefficient, the more chance on squeal.

I have chosen for the Pagid RS15, now called RST3 irrc:
https://www.jaguarforums.com/forum/x...ke-pads-79003/
They have an amazing stopping power already from cold (and wet discs in rainy weather), but these are race pads, so can(/will) squeal. They also eat discs for breakfast. Something has to give of course for the high friction coefficient.

Next to better pads, I can highly recommend the Michelin PSS, best tire I have had so far.


Here is a chart from Pagid that shows the characteristics of their pads:
http://www.pagidracing.com/products/characteristics/

 

AP Rotors and Calipers would be quite fitting for a Jaguar.

AP Racing is a Coventry, UK-based company and that every Formula One Championship since 1967 has been won using the company’s equipment (according to their site).

 

If anyone is interested in upgrading to the Alcon braking system that came on the XKR Portfolio I have the complete set available:


https://www.jaguarforums.com/forum/p...lipers-118733/

 

GREAT reply, Thanks! My brakes are actually great but they don't look the best, calipers that is. Not sure If I want to paint them or get covers. I would pay the cash for great brakes and calipers. Any ideas? Thanks in advance. Chris.

 

I'll look into it. Thank you for the advice!

 

Do not buy covers. Best solution is to have them powder coated, which you are essentially rebuilding the calipers. Powder coating is not expensive.

Next best is painting yourself while off or on the car. Not rebuilding the caliper

 

Thank you for the advice.

 

I had the grey powdercoated calipers but wanted something a little more showy. I could have had them re-powdercoated but I didn't want the car off the road for a few days so I had them painted red instead. Came up well, though powdercoating is a much better look I think.

 

What is wrong with the MGP Jaguar aluminum powder coated covers? In my humble opinion Jaguar calipers are not the best looking regardless of color unless they are Bembo or Alcon, simply because they look like the millions of other generic calipers on almost all cars on the road. Some of the car makers who do get it right are Mercedes, Porsche, etc.

 

OK I have an idea!

The S-Type front brakes from 2006 onwards are the same as what's fitted to the 4.2L XK, 326mm (part numbers are same for discs, calipers, mounting brackets)

The vertical links on the late S-Type and early XK were the same (shared part number) so the caliper mounting points are the same.

Some Lincoln guys fitted later model S-Type R (non-Brembo) front brakes to a Lincoln LS, and they bolted straight up. Lincoln LS Big Brake Kits

The 400mm 6-piston Alcons from the XKR have been fitted to XJR's without issue, and the front brakes from the S-Type R and XJR are the same. The parts are interchangeable. So are the Lincoln LS ones too it seems.

StopTech makes a Big Brake Kit to suit the Lincoln LS; 4-piston calipers, 355x32 rotors



So the Lincoln LS kit should also fit on the front of the 4.2L XK

355mm rotors are the same size as what's fitted to the 4.2L XKR, so you'd be able to get the correct size dust shields as spare parts.

OR the another way to go about it would be to take the complete 355mm front brakes off an S-Type R (VIN N52048 onwards), X350 XJR (VIN G49701 onwards) or 4.2L X150 XKR (whatever VIN)

EDIT

Here you go, Porterfield lists the Stoptech kit as suitable for the S-Type. If it fits the S-Type it fits the 4.2L XK as well http://porterfield-brakes.com/produc...roductID=11747

 

One of the more interesting and possibly valid concerns is that the covers allow the calipers to heat up more rapidly, and prevent them from cooling as quickly as those exposed to ambient air.
I have no facts to back it, but I have heard it enough times (and it hints of common sense), to give me pause... Heat is my brakes enemy...

Just food for thought...