Evening all

I am a confirmed XJ fan - my daily driver is a 3.2 XJ6 which I am very happy with. I also own a Range Rover Sport 2.7tdi or rather did own one - bought cheap, runs fine but peeling lacquer, needs new tyres etc. so bought it on a bit of a whim just over 2 years ago, stuck it in the driveway intending to spend some money on it and fast forward 2 years its still sat in the driveway. So, I have sold it. Was only interested in my money back and found a JLR enthusiast near me who has offered me cash plus two cars: an XJ8 3.2 in nice condition and an XJR (X308) 4.0 supercharged with front end damage.

Despite my wife not believing me I really didn't want to end up with these two cars but thats life!! So what to do with them? The million dollar question would be how difficult is it to do an XJR to XK8 engine swap? I don't mean the spanner work - I am confident I can get it to fit but what needs to be done in order for it to actually run? I realise I'll need to change the gearbox and probably prop shaft (?) since I know the XKR runs a Merc box but as far as wiring etc. is concerned is it plug and play or plug and cry?

By the way the sensible thing to do would be sell the nice XJ8 or use that and sell my XJ6. I honestly don't think I could part with my XJ6 having spent so much time and effort with it. Then break the XJR for parts. But then again I haven't got to the ripe old age of 43 by being sensible.

Thanks in advance!

 

yes you can if you don’t value your time. you can even build an x300 out of a 308 shell and vice versa, it’s been done

 

The wiring harness and electronic modules will have to transferred, probably instrument pack. I'm sure others can add to the list.

 

Exactly, it's been discussed before and this is usually the consensus.

To add to the other things mentioned, couple things off the top of my head are the fuel tank (XJR has twin fuel pump, I'm not sure if it's a different tank, or just the fuel pump holder, and related wiring/relays), supercharger cooling system (hoses, intercooler pump, supercharger radiator, wiring for SC pump). Things get even more complicated if one car is an AJ26 (cable throttle) and the other is an AJ27 (drive-by-wire throttle).

Now the other thing to consider, are you just doing an engine swap, or might you as well swap the XJR suspension (and brakes) over onto the XJ8? And, if doing so, are you gonna refresh the suspension while it's out, make sure all the bushings and bearings are pristine? These things do tend to snowball. The rear subframe is actually a fairly easy thing to drop as an assembly though. Undo driveshaft, brake calipers, parking brake, 4 bolts at each upper spring pan, 2/side forward bushing bracket bolts, 1/side forward bracket bolt, 1/side rear truss upper bolt, and it's out as one big bulky piece.

If you haven't yet, you should get on jagrepair.com, download the electrical guides for your model year(s), and compare the differences in some of the schematics between NA and SC cars...