131mirafiori forum

Have a look and keep the drooling to a minimum...

http://cgi.ebay.it/Fiat-131-Rally-Abarth_W0QQitemZ280056865312QQihZ018QQcategoryZ18305QQrdZ1QQcmdZViewItem

Has anyone seen it, in "the flesh", so to speak?

Beautiful rear axle location device, is that a "watts" linkage?

Why would we be drooling?? This car is NOT an Abarth in any sense of the word.

OK, it's a 131, and OK it has independant rear suspension, but not the Abarth fitment. It's only got an 8 valve twin cam as well, and the advert says that it was once a 131 Special, so if anyone is planning on rallying it I hope it has had plenty of additional underfloor strengthening applied.

I would steer well clear of it.

That's a very solid rear axle (with strange linkage instead of a panhard rod) ...  :-\

(http://i15.ebayimg.com/06/i/000/7c/a6/7d6e_1.JPG)

In fact with the strange pivot on the differential casing I cannot see what stops the axle from moving from side to side  ???

Ok, I've done my homework and looked it up. The strange arrangement is a Watt's Linkage which is meant to be an improvement on the Panhard rod as it gives pure vertical motion to a beam axle as opposed to the arc created by the Panhard rod. Here's what Wikipedia has to say about it:

Watt's linkage

The Watt's linkage was invented by James Watt (1736--1819) to constrain the movement of a piston in a steam engine to move in a straight line. The idea of its genesis using links is contained in a letter he wrote to Matthew Boulton in June 1784.
(http://content.answers.com/main/content/wp/en/thumb/6/6b/180px-Wattslinkage.JPG)

I have got a glimpse of a method of causing a piston rod to move up and down perpendicularly by only fixing it to a piece of iron upon the beam, without chains or perpendicular guides [...] and one of the most ingenious simple pieces of mechanics I have invented.
It is important to remember that this linkage does not generate a true straight line motion, and indeed Watt did not claim it did so. In a letter to Boulton on 11th September 1784 he describes the linkage as follows.

The convexities of the arches, lying in contrary directions, there is a certain point in the connecting-lever, which has very little sensible variation from a straight line.
The Watt's linkage is also an automotive rear suspension designed in the early twentieth century as an improvement over the Panhard rod as a means of locating a rear beam axle of an automobile relative to the body and preventing relative movement side to side. Whereas the Panhard rod is pivoted at both axle and body forcing the axle to move in an arc, thus introducing a sideways component into the vertical movement of the axle, the Watt's linkage ensures pure vertical motion.

It consists of two almost symmetrically arranged long rods mounted one at each side of the chassis and running parallel to and behind the rear axle, where they attach to the ends of a short vertical bar whose center is mounted to the center of the axle and which is free to rotate in the plane at right angles to the automobile's longitudinal dimension. As in the Panhard rod, the sideways arms themselves are free to pivot vertically at either end. Thus, each sideways member acts as a shorter Panhard rod mounted to the center vertical member providing lateral location. In contrast to the Panhard rod's action, however, the sideways components of the motion of the two arms as they pivot around their outboard mountings cancel each other in their effect on the axle and are instead taken up by the center member's rotation about its axis.

 In the 1998 Ford Ranger EV, carbon fiber leaf springs support a De Dion tube located by Watt's linkage while the motor/transmission is attached to the chassis.

(http://content.answers.com/main/content/wp/en/thumb/9/90/500px-GSFRRearViewUnderCropped.jpg)

Me again ! ;)
I just noticed that the spare wheel well has been removed from this car giving a lot more room for the exhaust silencer

(http://i15.ebayimg.com/06/i/000/7c/a6/7d6e_1.JPG)