Jag Rear End-Width

[Route 66]

Hi Kyle,

Thanks for the responses. I am concerned about the strength of shortened components and it is a priority. Some recent posts I have read are a bit scary. Some blogs make out the Jag gear to be like a truck and it seems widely used by hotrodders etc but finding some experienced can be difficult. There seems to be some leads on brand new parts from the states in some blogs I will check out. If I can find a diff centre in 3:54 with an LSD my brains trust at work are confident they can rebuild it without having to go a Diff specialist which would use up some cash.

Thanks


Route 66

Originally Posted by kyleb

I would use the arms but don't bother with the original axles. I know a number of people who have snapped them. Use the ends and have the axle made by spicer or a tail shaft specialist to the correct length using the heavier unis and then you can forget about them.
The problem with the JAG rear is availability of new parts. I rebuilt mine with a new crownwheel and pinion from Dennis whelch motorsports in the U.K and fitted an Auburg gear LSD clutch pack. It is now pretty much indestructible but took some working out.
That's not to say you can't get a good second hand unit that will last ages, just food for thought in regards to longevity and how much power you will put through it.

[Route 66]

Hi again folks,

Since posting the orginal query I have received some good advice to my various questions (thanks!!!) and also done some more research. I have not been able to track down a XJ6/12 III rear here in Brisvegas with the desired ratio (3:54) and/or LSD. Seems I can get it in bits down south in Melb but then would most likely need a visit to a diff specialist $$$ to swap gears etc plus freight blah blah. Then I ran into the headache that I could not find anyone up in my local area to shorten the Lower Control Arms? Draiveshafts are no problem - curious? The Qld Cobra Club connections have come through with a recommendation on the shortening issue. From posts I have read about LCA failures and one in particular which lead to a crash I am concerned about the strength and safety issues.

I have received a lead from OS about a set of E-Type Shafts and Control arms plus also a XJS diff centre with 3:54/LSD. I am not sure if this all can be mixed and matched? A local wrecker is adamant that the XJS Diff centre will be interchangable with XJ6/12? Peter R did say the E-Type (S3) gear was ok especially because it was already narrower but wasn't too confident about the XJS crossover? In theory it seems ok if it all worked together? If it was local it would be a big deal but the parts are a long boat ride away. The impression I get is if you ask a local (OZ) wrecker about E-Type parts they either laugh or you here the cash register ringing in the background. It is not all about the money but every couple of $'s I save puts a beer in the fridge in the shed for those long hours.

At the end of the day the outcome I am looking for is 3:54 LSD narrowed to get required offset for a slight dish on rear with 9" to 10" X 17" 's. (and strong & safe!!!)

The theory:- Get Local XJ6 complete rear - (cheap) -for brakes, hubs loose-ends. Source E-Type Shafts & LCA's and marry up to XJS 3:54 LSD??? (No shotening & no trip to Diff shop just near seals etc.)

Does any one know the answers????

On a side note I followed-up a thread on aftermarket lower control arms from the US but the business no longer operates.

Regards



Route 66
Not so sunny Brisbane Qld

[Rebel1]

Route 66, Did you try Hardy Spicer at Eagle Farm for the shortening of the drive shafts?.

Mine were shortened by the Kit supplier in WA and the tubing used is 75mm OD.

Have you spoken to Scott Hampson regarding the shortening of lower control arms?. He may know where you can get them shortened. He has worked on many many cobras with Jag suspension.

His site: Welcome to Venom Custom Fabrications

Remember any mods to suspension bits need your engineers approval.

[Route 66]

Hi Rebel1,

I did contact Hardy Spicers and they are happy the shorten the Axles/Driveshafts but wont touch the Control Arms. The other Drivesaft shops in Brisvegas were either the same or not sure. Through the Qld Cobra Club I have made contact with Scott as you mentioned and he is sidetracked at the moment but says he will be able to look at for me in a the not too distant future which sounds ok.

The whole shortening scenario seems a bit of a negative for both compliance, cost and reliablility hence my query about being able to mix E-Type bits. To a degree I would however think that a well engineered job would be as strong if not stronger?

Thanks again for the feedback - I am learning fast and enjoying the challenge.

Regards


Route 66

Originally Posted by Rebel1

Route 66, Did you try Hardy Spicer at Eagle Farm for the shortening of the drive shafts?.

Mine were shortened by the Kit supplier in WA and the tubing used is 75mm OD.

Have you spoken to Scott Hampson regarding the shortening of lower control arms?. He may know where you can get them shortened. He has worked on many many cobras with Jag suspension.

His site: Welcome to Venom Custom Fabrications

Remember any mods to suspension bits need your engineers approval.

[Rebel1]

Originally Posted by Route 66

The whole shortening scenario seems a bit of a negative for both compliance, cost and reliablility hence my query about being able to mix E-Type bits.

There are a lot of Cobras running around in Bris with shortened lower arms.

I've yet to hear of one having problems.

I'm surprised Peter R didn't refer you to somebody to shorten them.

[Chris L]

G;day Routte 66;
My 2 cents worth.........

If the job on the control arms is done properly, you wont have a problem with strength. Be sure who ever does them uses a jig, one of mine was out 4mm and made getting everything pointing in the right direction impossible without shortening wheelbase on one side of the car !!.
As for the diff, I sold a 3;54 lsd centre about a year ago and replaced it with a detroit soft lock centre ( to suit Dana 44 from memory) that was second hand (done 30klms) from an American friend I contacted through these forums. He let me have it for $300 which I thought was excellent.Have a good look at your drive shaft splines for wear. New bearings and seals thoughout, and some very skilled help from some mates at Ford performance Racing saw it all go together nicely. Could not be happier with the result. I would also strongly advise to go with outboard rear brakes if you can, set a mechanical handbrake assembly and ditch the complete inboard rear calipers and rotors.

I dont ever want to have the diff out of the car again, its a Python Kit and its not much fun getting access to some areas, but I imagine that may be a common deal.

Cheers
Chris

[Route 66]

Hi Guys,

As an update to my Jag Rear end query, from the start Peter (DRB) told me if I could find an E-Type rear it would solve my width and narrowing issues. He said they were rare and expensive but worth a try. First couple of guys laughed but I made a few enquiries around various sources and Gary from JagAyre Melbourne found me a Series II E-Type 3:31 Posi complete rear in pretty good nick. Price was cool, only $200 more then one local guy had quoted for an XJ6 LSD rear +$200 frieight. It has just arrived from Vic and is as described, has the larger later style brakes which are in better condition then the brakes on the Series III XJ6 front end I have. Diff has a little backlash but virtually no oil leaks? Surprising from what I've seen of any Jag rear ends. While I was looking for a 3:54 this is a reasonable comprise but the main bonus is no narrowing required. That had been a headache just finding someone to do it in Qld (Cobra Club did come thru there though) and also burns quite a few dollars. The hub to hub width issue still has me puzzled I must admit. This rear is just under 54 & 1/2" hub to hub unloaded and I would guess at normal ride height would add just under an inch to be about 55 & 1/2", this is pretty close to the 56" I've been told I needed to cut the XJ6 down to. unfortunately the various Jag forums only talk track and not hub to hub specs but it matters little now I guess as I have it here sitting on the bench.

Hopefully the diff won't need a complete rebuild but we shall see. Very likely there would be a roll of the dice with any XJ6 I would have found. It a little older but aren't we all.

Regards


Route 66

Ps: Hopefully striping it down won't be as big a pain as the front end. I still have sore knuckles from the springs and ball joints.

I must admit I can't wait to get the car sitting on wheels, that we be a hug milestone!!!!