Does that sway bar work?

KLR250 wrote:

Its hard to beleve it would do much being so close to the control arms inner pivots

it is kind of counterintuitive.  yes by moving it in toward the pivot it will have less effect on the suspension, BUT the sway bar arms are shorter so they will be much stiffer,  and I imagine it will be similar to bigger ones as the two facts will counter balance each other.

as to some pix I have tones of them and will post some when I have a little more time.

Ralphy wrote:

I understand shorter equals stiffer. But it loses leverage and motion. So it would seem to me it better be way stiffer.

Think of a sway bar as a torsion bar (basically what it is):

1. The shorter it is the stiffer it is. 
2. The fatter it is the stiffer it is. 
3. The  shorter the arm between the "torsion" section and the end link the stiffer it is.


On the flip side as you pointed out the further out on the LCA the bar mounts the less leverage the LCA will have on the sway bar and the more leverage the sway bar will have on the LCA.  As the mount moves in closer to the pivot the leverage the say bar has on the LCA is reduced and the leverage the LCA has on the sway bar is increased. 

in this particular set up the mount is about 2/3 of the way between the inner pivot and the shock mount but the arm between the "torsion" section  and the end link is about 1/3 the length of a typical sway bar. 

All that said I would guess that the force applied to the LCA by the sway bar would be comparable to a full  size sway bar of about 1/2" diameter and when you think about the Jag being luxury first and performance second that makes sense especially since many of these rear ends don't have a sway bar of any kind. 

well thats enough rambling from me feel free to tell me I have no Idea what I am talking about because that is always a possibility.

For a good idea of whats out there I like this article Hot rod put together.
http://www.hotrod.com/howto/hrdp_0712_irs_for_musclecars/index.html

The first half of the article is all about the IRS unit Ford designed for the classic Mustang back in the 60s.  Back then this unit used a Jag diff but the guy recreating them now is using a ford 8.8

classic Mustang IRS


The DVS kit has been on the market for a wile and allows the user to install a modern cobra Mustang IRS in to a classic Mustang.  the biggest down fall to this is that you cant really narrow it up.... well at least not with out major changes.

DVS Mustang IRS


Once you get past all the tubing I believe this unit is basically a Jag nock off
BLUE MOON CONTROL FREAK SUSPENSION


the next three are basically all chromed Jag units.  thay have been upgraded to use different center sections and seam to have some adjustability.
HEIDTS HOT ROD SHOP


SCOTTS HOT RODS


KUGEL KOMPONENTS


I find this last one most interesting.  I think I like it because it is so different than everything else.
TEAM321

Wow Ralphy, that looks like quite a build

Daze some here have also not seen what Mickmate (Nick) has done with a Jag IRS. Nick gets four stars also! LOL

http://www.clubcobra.com/photopost/showphoto.php/photo/66830/ppuser/10964.
http://img121.imageshack.us/img121/434/picture001.mp4
http://img96.imageshack.us/img96/8092/picture003.mp4

Here is the watts conversion on a factory hub. Scroll down to the pic.
http://www.clubcobra.com/forums/contemporary-classic-forums/85616-contemporary-cobra-watts-linkage-8.html
More pics!
http://imageshack.us/photo/my-images/194/watts011.jpg/
http://imageshack.us/f/201/watts020.jpg/

Last edited by Ralphy (5/19/2011 6:33 am)

here is a few more I found in another online article

wow, theres some nice IRS setups here, lots of bling thats for sure

Day here's a T5 I saw.
http://s587.photobucket.com/albums/ss311/Willy12_2009/?action=view&current=MustangKlausT5-1-1.jpg

I had found it on line. I think it's the same car in the video I had found. It comes up in some obscure search. If you search, Mustang, T5, IRS, etc... It will not come up. I found it in some picks I have saved.

are you talking about this piece minus the differential?

if so you would have to go to outboard discs but other than that I think you are right it should be an easy swap

Yep, that's what I am talking about. Shouldn't be to hard adapting this to any framed car chassis or am I missing something?

Ralphy, I live in Turkey and parts importing that big is a real problem!!!!!

Mustsed

KLR250 wrote:

Heres an IRS unit a mate is thinking of fitting to his falcon, Looks quite nice, Track is 57.30". Its from a MX81 Toyota Cressida

The US got the MX83 at the end of the Cressida run here, I don't know how similar the rear suspensions are.

Never got the MX81 so far as I know.

here is a few more pix I found moving posts from the old forum

JEM wrote:

The stock Jag IRS uses the trailing arms to induce roll understeer by pulling the outside wheel forward, and since the lower arms are (unlike so many later designs) rigidly pivoted to the diff housing via roller bearings this ends up pulling the entire cradle forward at the outside wheel.

Street-rod types rigid-mount the diff but ditch the trailing arms.  Racers run trailing arms with inner pivots coaxial to the LCA inner pivot axis to get rid of the induced roll steer.

This guy appears to have a rigidly-mounted diff case but retains the stock trailing arm orientation.   

I wonder how well it held up once the car went together.   It seems to me he'd have either broken parts or ferocious roll-bind.

I agree.  you would think that would cause all kinds of binding.  thing is I have seen a lot of people set there Jag IRS units up that way.  Especially hot rod guys.  The front leaf spring mount seams like the perfect place to mount the trailing arm so they do with no regard to the different arcs the arms travel at in relation to the wish bones.  When you ask them they usually answer and say there is no bind.  the only thing I can figure is that the bushings are soft enough and the difference in arcs in minimal enough that the bushings can absorb the difference.  If you ever look at a stock Jag trailing arm the bushing is a flat rubber piece almost 4" across.  that much rubber would absorb so much flex that I wonder how much, if any, understeer was actually induced in to the suspension??   

I went with the "Racers run trailing arms with inner pivots coaxial to the LCA inner pivot axis to get rid of the induced roll steer. "  method because I didn't want to run big bushings.  In this picture you can see my inner pivots on my pinion support, but at the point the picture was taken I had not yet fabbed up the arms


The best solution to Jag trailing arms is the one that Mustsed talked about wanting to do and then Ralphy brought us pictures of from the Cobra forum.  Watts link