Sparky's winter/spring/summer/autumn work

Interestingly this car was copied from 808D, which now has a Jag diff, but according to Bill Price who was in charge back then the car had the stock De Dion setup and never was raced with a Jag diff..
My mate who used to race a P6 in the local Classics used a setup with a wishbone and the DeDion tube, except he used an Alfetta transaxle in the back. The rules at the time required that the suspension utilised the factory hard points if it was modified away from original.


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Any update on this?
Nope :oops:

I have been doing a few things but have been busy at work and have a sick family member so time is a little short.

The diff is however in the car now, and although I forgot to put oil in it, I don't think it has to come out again :)

I'll sort some piccies out if I can :)



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I have managed to get the brakes sorted. The P6 handbrake cable ends are of a similar size to the round fittings of the jag calipers. After a bit of pondering, I drilled out the forward spot weld and prised the jaws open then managed to force the Rover ends in. I then used a small nut and bolt to replace the spot weld, just in case I need to replace the cable at some time. Happily, they fitted exactly with no play at all :)

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Thing is though, handbrake linkage is around 80mm wider than Rover one, so the handbrake inner cable is now 80mm too short :confused:. I had a look at the clevis at the front end of the cable and discovered that it was screwed onto a short threaded piece. I found a short piece of threaded bar the right size and a connector, then put the clevis back and yes, it works


I have bought a pipe flaring kit that actually works and made up the brake pipes, leaving a flexible piece to connect to the original pipework on the car.


I torqued up the bolts on the plate which held the front mount in and managed to crush the crossmember :eek:, twisting the plate at the same time. I then had to make up a puller to get it back to original, then set about it with some panel beating hammers. This was quite a set back to be honest, but it appears that most of this crossmember is made out of an old Chieftan Tank, but the small bit at the front, up to the tunnel is made out of wax :mad:

I took the bolts out and using studs instead managed to get a nut each side of the metal top and bottom, so 4 nuts per side to give it some support. I then used a bit of the 5mm box section to remake the plate and put it all back together. That should do it.

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Now to try and stop the front of the diff from twist upwards under acceleration, I drilled a couple of 18mm holes into the suspension crossmember. Then cut two short lengths of 18mm OD steel tube and tapped them in. Got them just right and had them welded into place.



These will hold two 14mm studs which can be adjusted for length by just doing up/undoing the nuts.

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Back in the car, with a couple of struts I made from some 12mm studding and 15mm tube it is all very solid :)

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Just need to get it all adjusted up, then tighten everything up and hope it works.

Oh, and I added a short piece of 10 x 20mm box section at each side on the front, to complete the cage. I couldn't get them both in same place so they are staggered, but I don't think that will be coming out of there in a hurry - so happy with that.


PS new propshaft and shortened half shafts have arrived back, so next job is to fit them and hope I have the measurements correct - what could possible go wrong ? :)
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The propshaft needed to be 30cm longer than the manual one (I have a spare manual prop), and after discussions with the drive shaft specialists I went for the larger tube as well. I did discuss going for a 2 piece version with the bearing mounted on the suspension cross member but they seemed to think that a one piece would do just fine.

I then got the old diff out and put the driveshafts back on, them measured from tip to tip.


I then did the same with the new diff and found a difference of 65mm. I had measured both of the diffs earlier and found a difference of 64mm. I did read somewhere that the diffs were 38mm different and therefore to shorten them by 19mm, but my measurements meant 32mm? So here they are, a 3" prop and two 32mm shortened driveshafts, ready to fit.


Prop bolted straight on, but I couldn't get the bolts to go in from the back whatever I tried. I did think of removing the input flange, but decided against that and just put them in back to front.


Then got everything torqued up and refitted the exhaust, which was more difficult then it sounds. I had to remove one of the struts to get it in and still had to wrestle it for around half an hour. Still, it's in now, but the exhaust is a different shape than I remember, and the strut will have to go straight through the silencer :oops: There's a little problem for later :)


I have managed to get a brake proportioning valve and after a brief search under the front carpets, I found an existing hole in the centre tunnel, possibly something to do with the old auto box or something the previous owner had fitted. I made up a washer to suit, bonded it in and fitted the valve there.


I have removed the brake pipe from the adapter under the servo to the joiner in the centre tunnel, and am in the process of plumbing it all in.

Not much more to do now :)



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Are you going to have to delete the middle exhaust box to enable you to fit that strut as you had planned? Sorry to be dim, but what are those struts for, exactly? What is the silver reflective material you lined t he underside of the tunnel with, and what did you attach it with? Apologies if I already asked you that, I've forgotten.


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Not quite sure what to do with the exhaust, it's under ponderance now :)

If you look at the diff from the front, the engine turns it clockwise, so if it gets any resistance (e.g. inertia from the weight of the car) the diff will tend to try and turn clockwise, putting force on the mountings. Rover put a stay bar from the chassis across to the diff to relieve this. I still have to sort that bit.

Also, because (looking from the right hand side of the car) the diff turns the wheels in a clockwise direction, the diff itself will try to turn anti-clockwise, and the more resistance, the greater the force. Rover sorted this by fitting an extension to the diff and mounting the front of it onto a rubber mount. This rubber mount is upside down if it was taking the weight of the diff, so it's there to relieve the upward force of the front of the diff. The front of the jag diff is a lot heavier than the Rover one, so I have put the rubber mount right side up to take the weight. Also the Jag diff is much shorter so will produce even more upward force (the lever is shorter) and there is more power from the Engine so producing even more :oops:. The struts are there to control this upward force. I hope I have explained this correctly :confused:

The shiny stuff is a heat and sound reflective self adhesive sheet, just an extra bit of noise insulation.