So I have an 86 XJS that im working on, I know that the IRS has inboard breaks held on by a cage, was wondering what other IRS from other models with outboard breaks would fit in the cage for a clean swap? Years and models would be greatly appreciated!

 

I believe facelift cars 92? To 96 would work...good luck finding one.

why would you want to switch though? The inboard setup has less weight on the outside and yes maybe an extra effort to access things but it held up for decades before Ford re-unengineered it.

 

Outboard braked cars have a different differential ratio, thus different speedo ratio, ABS brakes (which your 1986 will not have, but you do not have to connect them anyway), and different handbrake mechanism and brake lines. They will physically bolt in, but these differences have to be dealt with.

 

Don't mean to be a stick in the mud, but I would leave the IRS as is in that 86. Drop the cage, give it a service, do some other stuff while your at it, and get it down the road. Once the new calipers, pads, and ebrake is set up - raising the rear end and swapping out the pads is not a big deal. Then, inboards is a bunch of language to do with weight distribution, centerline, handling and all that stuff. Knowledge, outside my wheel house.

There is a guy I love and respect,,, happens to live in my global neighborhood,,, who swears by the change (not sure about the whole cage swap aspect you're suggesting) of conversions to outboard brakes and he might be able and willing to help you a heap and walk you through the process... Goes by the name of icsamerica on the forums. Lol, he'll convince ya ta DO it!!! But I would resist,,, just to get him going, lol

 

With all the talk about the horrors of inboard brakes when the brakes break, I do wonder how often you need to access them for more than pads. When my car ('92, still inboard; the change wasn't until the following year when at the same time (roughly, from memory), the door handles went to modern flaps) needed the rear cage dropped and the brakes serviced, it was around $500. I'd pay that every half-dozen years or so to avoid the hassles of trying to replace the whole lot with outboard.

 

Do it all with EBC vented slotted rotors and red pads, you shouldnt have to DO any work for many many years. Paint everything in anti-rust high temp caliper paint for preventative measure...Use acdelco crap and find yourself dropping the cage often.