I'm confused. Series I, II, III XJ6 outboard rear discs how?

[ewokracing]

So I've got a p6b which I've had the unfortunate chance to lie under for the past year going through the diff, rear brakes etc. Never ever again. It's a horrible design from a maintenance point of view. Bleeding the rear brakes has been nothing but a cnt.

I managed to pick up an uber cheap complete XJ6 rear end. One of the guys at work has a few rear ends lying around as well for his Chev V8'd XJ's. We both want to convert them to outboard discs.

Has anyone successfully done it? I have seen threads around where people talk about doing it, but never a step by step guide or build thread about it.

What bits fit from later jags and what need to be customised? (obviously the Rover is a fair bit different).

What is the jag model that I should be looking out for to grab another complete diff setup from? (XJ40?)

thanks!

[sowen]

I think you'll be after XJ40 stuff, at least the outer hubs and driveshafts if you already have a diff, and depends on how you want to fit it all in, entire Jaguar suspension or retain the Rover suspension?

[ewokracing]

Hey Sowen

probably a mix, more like what the guy in the US did with his five litre car. I think I'll end up using some of the jag frame, but mostly complete fabrication using a custom frame and as many brake and suspension jag bits as I can get away with. I want to try and get it so that I can run decent dish wheels on the back too.

[sowen]

Have you looked at the Irish rally P6 then? They've used a complete narrowed Jaguar IRS unit I think in a custom cradle, very good write up too

[volospian]

XJ40 and X300 use outboard brakes and are largely interchangeable. X308 does too, but the diff is a different design with the input shaft central, rather than offset like the xj40 design.

Have a look at the jag racing site for the various diff ratios used in different cars (on home page, scroll down a bit). May be useful to help you find a decent doner. www.jagracing.co.uk/

[brennon]

late xjs is the one you want

[ewokracing]

Sowen, yep, I read it and thats roughly what I'm aiming for.

volospian - ta for the link, off to do some reading.

brennon - yeah for the LSD!

[sowen]

Cool, are you going to do anything on the front, in my experience and that of the Irish rally car there was a heavy brake imbalance front to rear. If part of you're plan is for alternative wheels, I'm wondering if it's worth looking into getting the complete Jaguar front hubs and brakes too and seeing if there's any inter-changeability there, as the big Jaguar 4 pot calipers fit the Rover upright, maybe the hubs could fit with different bearings?

[chairchild]

from the look of this:



Nab the hub carriers + hubs, and use the rest of a normal jag IRS setup. Job jobbed

[ewokracing]

Aug 15, 2014 7:22:57 GMT sowen said:

Cool, are you going to do anything on the front, in my experience and that of the Irish rally car there was a heavy brake imbalance front to rear. If part of you're plan is for alternative wheels, I'm wondering if it's worth looking into getting the complete Jaguar front hubs and brakes too and seeing if there's any inter-changeability there, as the big Jaguar 4 pot calipers fit the Rover upright, maybe the hubs could fit with different bearings?

Yep, you've read my mind. Better front brakes with vented discs will be a start. My car is missing the Australian market chassis strengthening plates as well so I want to do that at the same time.

Hmmm, I didn't know that the Jag calipers went onto the p6 upright. Interdasting. I have access to cluey people that can make hubs etc (at a price), so I was hoping to be able to "narrow" the hub or something as well which would allow a more RWD offset front wheel than the +30ish offset required at the moment (same goes for the back really).

Aug 16, 2014 17:46:20 GMT chairchild said:

from the look of this:



Nab the hub carriers + hubs, and use the rest of a normal jag IRS setup. Job jobbed

Yes, that's what I'm sort of trying to figure out. Which bit do I use from an XJ6 and which bits do I use from the XJ40. XJ40's arent really around much in wrecking yards anymore (but XJ6 SI/III/III's are, go figure) so I need to sort of work out what I want and then source it.

One of the guys at work is converting THREE jag/daimlers to outboard discs, all have Chev V8's in them. I'm sitting back quietly to see how it goes with it

[sowen]

Aug 18, 2014 6:04:56 GMT ewokracing said:

Aug 15, 2014 7:22:57 GMT sowen said:

Cool, are you going to do anything on the front, in my experience and that of the Irish rally car there was a heavy brake imbalance front to rear. If part of you're plan is for alternative wheels, I'm wondering if it's worth looking into getting the complete Jaguar front hubs and brakes too and seeing if there's any inter-changeability there, as the big Jaguar 4 pot calipers fit the Rover upright, maybe the hubs could fit with different bearings?

Yep, you've read my mind. Better front brakes with vented discs will be a start. My car is missing the Australian market chassis strengthening plates as well so I want to do that at the same time.

Hmmm, I didn't know that the Jag calipers went onto the p6 upright. Interdasting. I have access to cluey people that can make hubs etc (at a price), so I was hoping to be able to "narrow" the hub or something as well which would allow a more RWD offset front wheel than the +30ish offset required at the moment (same goes for the back really).

Aug 16, 2014 17:46:20 GMT chairchild said:

from the look of this:



Nab the hub carriers + hubs, and use the rest of a normal jag IRS setup. Job jobbed

Yes, that's what I'm sort of trying to figure out. Which bit do I use from an XJ6 and which bits do I use from the XJ40. XJ40's arent really around much in wrecking yards anymore (but XJ6 SI/III/III's are, go figure) so I need to sort of work out what I want and then source it.

One of the guys at work is converting THREE jag/daimlers to outboard discs, all have Chev V8's in them. I'm sitting back quietly to see how it goes with it

Yep, the big Jaguar 4 pots bolt on, I can't remember which bolts I used, as the caliper bolts are different between the 2000 and 3500. What the Jag caliper does is sit further out so larger discs will be needed, I used Land Rover Defender vented discs which just by chance are a near perfect fit, the disc protrudes about 0.5mm from the pad, only needed to run the grinder over the caliper body against the disc bell to clear. Braking power is vicious . If going for custom hubs, then all the better as I had to have mine skimmed to clear the disc adapters.

Narrowing the Jaguar IRS to suit doesn't appear to be that big a job, well within the realms of a competent engineering workshop. I think the end choice of parts should be dictated by availability and best fit, the series XJ diff should be relatively easy to mount in he body especially if you need to make a custom cage, then the XJ40 hub carries have the appearance of being backwards compatible. If you were to be retaining the De Dion, then I'd suggest the XJ40 diff may be more suitable going by the apparent mounting points.

[brennon]

Xj40 seems excessive when late xjs bolts straight up, has outboard disks, LSD and an anti roll bar

[sowen]

Aug 18, 2014 11:02:21 GMT brennon said:

Xj40 seems excessive when late xjs bolts straight up, has outboard disks, LSD and an anti roll bar

What year did the XJS go to outboard brakes?

[brennon]

Aug 18, 2014 11:49:29 GMT sowen said:

Aug 18, 2014 11:02:21 GMT brennon said:

Xj40 seems excessive when late xjs bolts straight up, has outboard disks, LSD and an anti roll bar

What year did the XJS go to outboard brakes?

That I can't confirm for you as I'm unsure, here is an example- www.ebay.co.uk/itm/331231128508

[sowen]

Going by that you could almost completely assume that the outboard brakes are compatible with the earlier inboard type, but presumably it will be harder to find a specifically late XJS, especially in Australia?

[brennon]

I seem to have missed the Australia part! It doesn't seem peoples locations appear on my phone!

[ewokracing]

XJS' are still a bit of a collectors car down here, although heap beat up ones do pop up on ebay every now and then. I'll keep an eye out, I thought all XJS' had inboards.

[volospian]

If you only need the rear hub carriers, you can probably use anything from xj40 ('86-'94) through x300 ('94 - '97) to x308 (97-2003) as they are all pretty much identical where it counts. The hub carriers I used on my cobra kit, which is based on xj40 donor, came off an x308 as I originally wanted the 3.27:1 diff ratio, however the mounting is different between diffs and I had to source an x300 xjr diff (which has the same ratio, but also has an lsd, so they're harder to find and more expensive). However, the hub carriers, half shafts, etc. all fitted fine.

For the front end, the xj40 and x300 use the same setup, but the x308 changed considerably and is not compatible at all.