Jag IRS with Outboard brakes for Hawk?

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JohnO
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Jag IRS with Outboard brakes for Hawk?

Post by JohnO »

Hello all,
Is anyone familiar with the Ward Engineering outboard brake option for the Jag IRS? It is a fair bit more expensive but just seems like the right thing to choose. :D
Thanks,
John O.
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Roger King
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Re: Jag IRS with Outboard brakes for Hawk?

Post by Roger King »

Pretty familiar with it, yes. I designed it.

Basically it uses the stock Jag pick up points and mountings on Gerry's 'jaguar' chassis. Use an early type diff, any XJ6 E-type style etc.
But - it uses the later XJ40 hub carriers, hub, brakes etc.
The wishbones and driveshafts are shorter to allow for the deeper hub, and there are adapter sleeves for the later hub to fit the earlier wishbone pivots.
Just make sure Ed is shortening the wishbone in two places to keep the shock absorbers in the right place! From memory (and it's a long time ago), he usually shortens them on the inside end - he still needs to do this, but also needs to shorten the outer end. If he takes it all off the inside, the damper mount moves too close to the diff. You will also need the special hub adapters, see pic. This helps to make it more expensive!
Did 12,000 miles with this mod with no problems. You will have to fabricate your own design of mount for the front ends of the handbrake cables to the chassis.
xj40 rear 005small.jpg
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JohnO
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Re: Jag IRS with Outboard brakes for Hawk?

Post by JohnO »

Many thanks for the prompt response Roger. I've decided to go for it - Ed reckons sometime in Feb for delivery, so it should be soon after I get the body/chassis. Fingers crossed!

Gerry did question if the hub splines would fit the FIA wheels and I've asked Ed to confirm - although your comment below sounds like it should be fine. I'll also pass on your comments re' shortening the wishbones, but I'm sure Ed is on top of it. He also told me of the need to fabricate the mount for the handbrake cable.

Once again, many thanks - John o.
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Roger King
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Re: Jag IRS with Outboard brakes for Hawk?

Post by Roger King »

Is Ed supplying the bolt-on hub adapters? If so you should be fine.
Erm - did he specify which February? - joking (kind of). He does a great job.
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JohnO
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Re: Jag IRS with Outboard brakes for Hawk?

Post by JohnO »

Yes, Ed is providing the Special hubs. What diff ratio did you go for?

Thanks again, John
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Roger King
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Re: Jag IRS with Outboard brakes for Hawk?

Post by Roger King »

Depends on the gearbox. The best option is to use a T5, with modified 5th gear giving 0.73 od instead of the stock 0.68, which is too long. Modern Driveline will happily build this for you at very little extra cost. This evens out the ratios somewhat to make it all more useable. I'd then go for a 3.54:1 diff ratio.
If you're using a toploader, I'd go for a 3.07 diff, but these are getting quite hard to find.
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JohnO
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Re: Jag IRS with Outboard brakes for Hawk?

Post by JohnO »

From reading other posts here and elsewhere I'd decided on the T5 with 0.73 od and as you say, Modern Driveline are happy to fit this for a reasonable charge. So 3.54:1 powerlock is what I'll go for. Thanks Roger. :D
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Re: Jag IRS with Outboard brakes for Hawk?

Post by Magnus »

The last years of the XJS (1993 to 1996) have outboard brakes. Would this axle be possible to use? From what I understand it has both powerlook and 3.54:1 diff ratio.
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Re: Jag IRS with Outboard brakes for Hawk?

Post by Roger King »

Magnus wrote:The last years of the XJS (1993 to 1996) have outboard brakes. Would this axle be possible to use? From what I understand it has both powerlook and 3.54:1 diff ratio.
I really don't know, but I don't think the later type diff will fit Gerry's chassis brackets. I'd ask Ed, or Gerry.
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Re: Jag IRS with Outboard brakes for Hawk?

Post by Magnus »

Ok, Roger it´s not the XJ40 version I was thinking of. If that's what you mean with later type.
It´s the version shown in the link below I think would be a great choice.
http://en.wikipedia.org/wiki/File:1995_ ... bframe.jpg
Or is there a difference in this diff housings compared to older axels?
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