Great mod! With all that extra grunt you will need those discs!

 

Now that you decided to throw a Chev v8 in it, like thousands of others before you (boring). Why not make yours standout by adding Jaguar IRS to it?

Bob

 

Challenge accepted, but I request you put some skin in the game.

This weekend I will get the hub-to-hub spacing on the current 2HA axle; in turn your part of the challenge will be to find a Jag IRS with 5x5 lugs and a width that will allow me to still retain the fender skirts. Spacers are permissible but running without the fender skirts is not allowed.

 

I was able to spend some time in the garage tonight. First up, here is the brake caliper from a 2005 Brake Century.
These are sliding calipers, with a single piston on the inside of the rotor that clamps both brake pads between the rotor. The two bolt heads you can see are the sliding pins; the frame you see below that with the two threaded holes is the fixed bracket that is bolted to the upright.




This is v1 of the bracket I designed for these calipers, 3d printed with PLA plastic as a proof of concept. These are not road-worthy.


The "original" bracket from the guy on the other forum on top, v1 of my bracket below.


Checking fit without the rotor in place.
I have the spacing correct radially, but axially the caliper needs to move towards the center of the car.


I'll whip up v2 and print it out tonight.

 

Series 1 & 2 xj6 has 58” rear track the same rear track as the Mark 7 at 57.5 or 58. You can also play with the wheel offset as needed.

 

That's the right width but the lugs are 5 on a 4.75" circle.....

 

But with the 4.75 bolt circle you'll have a greater wheel selection.

You can also graft the 5" bolt circle on to the IRS hub.

 

So my brain has been chewing on this. I love the idea of the Jag IRS because (1) it has a smooth ride, (2) it makes switch the rear drums to discs much easier, (3) I'm pretty sure the rear end ratios are better than the 4.11 I have today, and (4) challenge!


So then I started thinking about what if I removed the stock Jaguar front end - the steering box, the torsion bars, the control arms, the uprights - all of it...
And in its place dropped in a Mustang II front suspension.


I'd get my disc brakes. I'd pick up power steering and more importantly a rack and pinion. I'd have 5 x 4.75" hubs at all 4 corners.

It's just an idea because I'd lose the stock wheels (I love the body color wheels with the chrome hub caps) and I'd have to cut into and weld the front frame.

 

We are all on the edge of our seats!
My own feeling is that a Mustang front end would be a step too far, I do not think it would add much once the discs are fitted to the OEM front suspension; and whilst a non-Jaguar engine is one thing, changing the front suspension and steering starts to move the car nearer to a home-made lookalike, rather than an updated classic.
But I LOVE the IRS idea and it would not be too difficult either. Plus more ratios than you can poke a stick at. Moreover, a future owner could reinstall a Jaguar engine if desired and if a mad purist, reinstall the discarded rear axle.
I was always a bit concerned about what would happen to the 2HA when an enthusiastic driver in 6th gear planted the right foot at lowish revs. I think that the V8 torque might well overwhelm the casing and internals.
Great project though: all the fun of enjoying it for us spectators with none of the pain!

 

I agree with you Greg. It's a balance act between upgrading/updating for reliability and maintaining the charm of a 70 year old car. The front suspension is a bridge too far; in the 800 miles I've driven the car I enjoyed the large steering wheel and the steering feel that is on the heavy side.

Sometimes I like to let the inner engineer out for some fresh air though

 

You should be able to get other steel wheels with the new bolt pattern right? Paint them in the appropriate color and refit the hubcaps. As long as they’re not alloy wheels you’ll have the right look.

Alloy wheels on old cars really annoy me. They spoil the look in most cases.

 

Today I decided it would be easier to check clearances if I pulled the whole suspension upright off the car and worked on a table.

I also narrowed down my choice of brake caliper to what was fitted to 1995 Dodge Grand Caravan's with the 3.3L engine and 14" wheels - part numbers 18B4360 and 18B4361



Not a great picture but this caliper will fit within the odd design of the wheel and nothing will need to be ground away - which was an important consideration.


I need to verify fit but this should be an easy bracket to manufacture. The original design from 25 years ago required part of the bracket to be machined away - I believe this bracket and caliper combo will eliminate that requirement.

 

Yikes, you are inching closer to the drastic, soul-changing modification I made to my Mk10 — electrification. You might as well think about it, for fun at least. E.g., transplant the rear subframe/drive unit of a Tesla Model S. You'd get the IRS, disk brakes, reliability (no oil leaks!), and the fastest MkVII the world has ever seen.

It's what the cool kids are doing these days! See Superfast Matt's Jaguar conversion videos. Or inCarnation's videos on converting a Porsche 928 (I'm not converting my 928, though)..

Note, however, that I think my Mk10 rides more smoothly than my Tesla S, as befits a stately plump British Saloon.

 

A Tesla swap doesn't really fit my use case. I like long road trips off the beaten path and between range anxiety and finding a charger in Shubuta Mississippi I think I'm going to stick with gasoline.

 

Understood. I made sure my car could do a round trip to the museum where I volunteer, comfortably (nominal range of 150 miles), but had little desire to go any further. Like most conversions, my car does only Level 2 (slow) charging. I rarely go on long trips even in my daily drivers. I enjoy the nest I've built at home.

===================

In said museum, by the way, the current exhibit is about Pontiac muscle cars. There are two engines on display. Looking at them, I think the only high-tech thing about them is manufacturability. That is, they otherwise seem quite primitive to someone who is familiar with a Jaguar XK and similar. But simple largely equates to reliable, doesn't it? You mentioned range anxiety; is there a short phrase for the anxiety we all feel about driving vintage cars? British vintage cars? AAA towing radius anxiety?

 

Curt,
Many years ago I had a long term hire car in NYC, and Pontiac Grande Prix, about 1975 model, 415 cubic inch, fom memory. Fantastic engine, car went like a train. Is that an engine you have on display?

As for a phrase for breakdown anxiety, not to my knowledge; but the large box of spares, wires, hoses, belts and tools in my boot (trunk) shows it is real!

 

Please don't destroy a classic Jaguar with a garbage electric motor.

Not sure being simple is really the key? They made so many of them that the problems became apparent early on and so did the fixes. We see this with Jaguars too but the production numbers are so much less that it take a longer time. If you have an S-Type or any older Jaguar all the problems have long since surfaced.

Those Pontiac engine were made by the millions. The VW flat 4 cylinder is another one. Massive production numbers and a huge after market catering to that engine. Even now decades after production has ended there is a large active market in both these engines.
.
.
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Pontiacs max'ed out at 455 cu in, but by the time they appeared the 1970's emission doldrums were underway The classic GTO engine was the 389, as in the lyrics of the hit "GTO" song by Ronnie and the Daytonas. I was a teenager during that era, but the car I lusted after was the Lotus Europa. Pontiac did try some high tech first among American companies, e.g., the first engine with - gasp! - an overhead cam. A six. Didn't last long - too expensive to manufacture, and not a V-8.

Sorry to be hijacking Thorsen's excellent thread.

 

I'm happy enough with the bracket that I designed to fit the Grand Caravan caliper that I sent it out to SendCutSend to have two made.



The holes for the brake caliper are sized for a M14x2.0 tap which will make installing the calipers super easy.



I'm neither an engineer nor a draftsman but it's important to be in close proximity to an expert.




I also spent some time rearranging and cleaning up the garage. The new motor/transmission will be delivered this Friday and I want to have the brakes in a good spot before I start working on the motor.

 

I did not realize as part of this thread that we could challenge Thorsen to ever more spectacular feature of engineering. Otherwise I would have urged, in the finest tradition of British cars, that if the XK engine was rejected then he should shoehorn in a 440 and figure out how to stop it overheating...
But to paraphrase Austin Powers, "that train has sailed".
(Apologies - Sunday night and probably had one glass too many)