Jag Jaguar IRS into a 46' International Harvester

Yeah, I saw several Cafone. I was looking for them to show my buddy who I took with me. He couldn't visualize what they look like exposed out of the cage. Yet again.... Not 1 Harvester at a car show I go to. I can't wait to get mine going!!!

 

This thread has been great as I'm getting a jag rear cleaned up to put under my Henry j, I forgot to measure the distant for making the shafts flat when mounted. Do you have an exact measurement on the flat bar you used? You said it was around eleven inches?

 

NOBODY???
That's a big call.

 

Yes, I did mine 11" center to center and the halfshafts are pretty much level.

 

10-1/2 for level lower arms, 11 for level halfshafts.
Anybody out there have any 354 or 377 gears for 79-87 Jags?
Need some now!
Thanks in advance.
Milton

 

a lot of people hear make the top shock mount ajustable,i had a popular where the shocks were mounted on the lower hub carrier shaft(longer of course)

 

There's a bunch of us in line for a better set of gears!!!

 

Need some opinions on the hub side bushing/rod end to be used for the trailing arms. Are the adjustable angle rod ends up to the task?
Example: http://www.kugelkomponents.com/zencart/index.php?main_page=product_info&cPath=50&products_id=184

Or should they be made by welding the threaded stud onto the DOM end at the angle required?

I will be using a spherical heim on the other end.

 

why not use heims at both ends? just weld the tabs to the trailing arms and cross member at an angle....

 

Maiden, I've been pondering this as well, and I'm not 100% sure which way to go either.
The length of the (long) trailing arm would make the arc deflection minimal, but ideally you would want the forward pivot point of the trailing arm to be on the same axis as the LCA pivot bolt.
I think the right way to do it would be as in the attached pic (not mine, but found it somewhere on the web a while ago). Looks like this guy used those fancy shmancy goodies that you posted the link to.

Dak

 

I thought about doing that as well. My plan on the crossmember is a little different. I plan on using two sticks of 2x2x1/8". They will sit at the width of the coilovers so I can come off the bottom of each for the upper coilover mounts. The pumpkin will be fixed solid to them, no bushing of any type. The 4 ends of the crossmember(2 per side) will not be welded to the frame rails, rather will bolt to the frame rails with possibly shackle hanger type poly bushings. Just like the rear in the cage, I want the whole unit to be able to drop out in 1 unit. This is also going to be a daily driver so my thought is that the bushings will help with vibrations and road noise entering the chassis. So the crossmember will be bushed to the frame. Then if I use the bushed rod ends like I mentioned, then the trailing arms will also be bushed. Next is the torque stays. They would need to be bushed as well. I plan on running 4. The two in the front will be angled 45* up/forward from the front tie bar to the frame rails. The two in the rear will simply connect from the rear tie bar up to the crossmember near the top plate. It will help tie the whole unit together but really is just for looks. I have an idea brewing for the rear view of the suspension that I'm keeping under wraps until I can show it. I started looking at all the different diff covers available for the D44's and Jags rears and didn't see what I was looking for, other than the Zombie head one available out of the UK. That one is ove 5 bills so forget that. So I came up with a different idea.

 

Don't care for that setup. He used them on the wrong end. He would have been better off just using spherical heims in those locations. Then using those near the hubs. That is what I am pondering doing. His torque stays are also not angled forward.
Fancy shmancy... lol
Good pic though, hadn't seen that one before.

 

his is also solid mounted so really he doesnt need the trailing arms at all. only needed if the rear is rubber mounted.

 

That's a huge debate as well. Much like so many other setup details with the Jag rear such as pinion angle.

 

I'd put them in regardless of rubber or solid mounting.
JM2CW

 

If the trailing arms aren't on soft bushings they will cause binding on the needle bearings. Even with them at an angle and long like that and the forward point level with the mount on the rear. As the half shafts go above level the distance between the end points get's longer as it does when they go below level.

 

In a light car, with an average power plant, maybe, but I'm sure there is a reason Jaguar put them in the original cars.

 

From another thread...

I actually ended up taking mine off after making a brace for the bottom of the diff.

 

I agree, i am going to brace the bottom of the diff and go with out the trailing arms

 

I'm not buying into that.
Have you any engineering or other evidence that this is what happens?
Set up properly, a triangle is formed and I really can't see how any of the 3 sides can change size and cause binding.
My mind is open enough to be changed, so convince me.

 

You are only thinking 2 dimensions when the suspension acts in 3.

It's basic suspension geometry really. As the suspension either compresses beyond ride height or extends the trailing arm end travels in an arc. This effectively pulls the half shaft forward on either compression or extension and causes binding.



You can read more about it here.

http://s-86.com/s-5linkrear.html

and here more specific to the jag.

http://www.tbucketeers.com/threads/my-jag-rear-radius-rods.12648/page-3

 

Jag used roller bearings on the lower arm to keep the fore-aft location of the arm rigid.

The trailing arms steer the entire cage assembly by pulling the outside lower arm forward to provide a bit of roll understeer exactly as you get with a Hotchkiss-mounted stick axle by locating the front spring eyes below the rear.

This was all by design. Jag designed in a predictable dose of roll understeer. It works by steering the entire cage on its mounts as if it were a stick axle. And this only works if the entire wheel-to-wheel IRS assembly is rigid fore-aft. No soft bushings in the control arms.

If you rigid-mount the diff and/or cage, using the stock trailing arms and mount locations will just pull and push on the control arms, it will bind, wear the trailing-arm bushing, and if made too rigid will eventually break something.

 

zman, I read the Tbucket discussion you posted last weekend. I stumbled across it doing research. It sounds, if I read it correctly, that the confusion was caused by some thinking he mounted his rod end to the half shaft, not the stock wishbone location. Once it was cleared up, all agreed it was fine.

If the trailing arm is aligned on the same pivot axis as the inner wishbone, it just ends up making a huge A-arm. I imagine the hub side of the trailing arm welded to the wishbone. Then a rod through the wishbone and outer trailing arm end. This would all pivot together as one. What am I missing? http://www.uk-hotrods.co.uk/v2/tech/jag_rear/tech_jag.php
3rd diagram down shows the rods in blue(inner pivot) and the trailing arms in red. Thus turning the wishbones into a giant A-arm. I can't see how it would bind unless the outer rod ends were not on the pivot axis.

If I knew it all, I would not be posting. I don't so it's why I am. I say that so that you understand I am here to learn. stating my thoughts and opinions and asking questions is pretty much how I learn. If I am wrong on my thoughts above, please explain what it is I'm incorrect about. I'm very open to correction. Again, thanks for the help guys.

As far as not running trailing arms, it doesn't matter if it will work or not to me. I like the look of them and want them in my design. To me, the more moving parts, the more sophisticated it looks. lol I would do some Watts Links if I knew more!
If done proper, even if they are not truely needed, I can't see how the trailing arms could hurt anything.

 

Your Binder is comming right along. Have you tackeled the brake work yet? I put a 9" posi under mine and am having a problem getting enough braking to get it stopped with the motor I put in. I'm running a stock master,but going to adual master to see if I can get it stopped.
I'll be watching to see what and how you do your brakes so keep wrenching-------your right about binders being a rare breed at shows, most of the time I,m the only one there.

 

The discussion isn't about using the trailing arms in the stock locations straight forward. It's having them set up with the outer end on the same pivot as the inner wishbones. Thus creating a lower A-arm.

Let's keep the discussion with the knowledge of the differential/crossmember being solid mounted in the chassis. Torque stays from the front Tie Bar, 45* forward & up to the chassis rails.
At this point, doesn't really matter how Jag did it because the whole suspension isn't going to be moving around. It's solid mounted to the chassis. With that said, and we can agree or disagree on the need of trailing arms when solid mounted, let's just discuss how the trailing arms CAN be properly used in the above configuration.

 

Hey Silver, been awhile. Not onto the brakes yet. I plan on crossing that path soon I hope. I planned on one of these but with a dual booster. http://www.southernrods.com/brakes/...edal-combo-kit-w-booster-master-cylinder.html

I'm gonna have the front and rear Jag power disc brakes so I can't imagine stopping being an issue as long as I get the setup correct.
Is your Binder done? I forget what all you used in it. A 9" out back. What about the front? What's powering it?

 

I am going for the best factory Jaguar brake setup I can which is why I am using late XJS (1993/4-1996) outboard discs - vented in my case. These swap in to any inboard XJ6/earlier XJS setup by using the XJ40 hub carriers, discs and calipers.

For posterity I have just measured the front and rear suspension widths for anyone contemplating using Jag suspension. These are from an outboard braked XJS but are the same as an XJ6 thru 1986 as far as I know. Front hub to hub 59". Rear hub to hub 61-1/2". Wheel center register is 2.904" give or take - so good for a 3" center hole wheel and the wheel bolt pattern is 5 on 4.75 but unlike Chevy they use 1/2"-20 studs - not 7/16". I need to change bolt pattern to 5 on 4-1/2" for my original artillery wheels, but other than that it is looking good....

 

Any photos of the brake swap? Did you leave the old rotors in place or replace them with some sort of spacers?

 

Just thought I"d let everybody know I've finally got my 3.54 gears--------Bought everything to rebuild IFS&IRS plus gears and e-type coilovers from John"s Cars, Inc. Dallas,Tx. (214-426-4100) Super nice man. First time out of shop yesterday in 2 yrs.
Thanks,
Milton

 

Congratulations, that was worth the wait. A very cool truck and different.