MacPherson Strut suspension

The MacPherson strut suspension was invented in the 1940s by Earl S. MacPherson of the Ford Motor Co.. It was introduced on the 1950 English Fords and has since become one of the dominating suspensions systems of the world because of its compactness and low cost.

Unlike other suspension designs, in MacPherson strut suspension, the telescopic shock absorber also serves as a link to control the position of the wheel. Therefore it saves the upper control arm. Since the strut is vertically positioned, the whole suspension is very compact. 

For front-wheel drive cars, whose engine and transmission are all located inside the front compartment, they need front suspensions which takeup very little width of the car.  MacPhersion strut suspension is the most suitable one.

This simple design does not offer perfect handling. Body roll and wheel movement lead to variation in camber, although not as severe as swing axle suspension. From a designer's viewpoint, its relatively high overall height requires a higher bonnet line, which is not very desirable to sports cars' styling.

 

<< Hyundai MacPherson strut  Like double wishbones suspension, MacPherson strut can be adopted in both front and rear wheels. In the 80s, there are many budget saloons employed Mac strut in all corners,  One such is Fiat's Type 4 and Tipo platforms, on which Fiat Croma, Lancia Thema, Saab 9000, Fiat Tipo, Tempra, Lancia Delta, Dedra etc. were based.  None of them was famous of handling.

 

Mac struts canbe made to go fairly well though, Both the Audi Quattro Coupe and The Subaru Imprezza emply it.

                                                             
                                                                        Mac Pherson Strut (1947)
 

Its new features was the use of a combination of the damper and the spring  as the pivot point for the wheels steering. 

This system has good roadholding capabilities for a very reasonable price. That is probably the reason why it is one of the most popular suspension system. It has been used for years by many car manufacturers including all the Ford range and is still in use today.
 

It may be the biggest step forward in the evolution of front suspension for the road car. Together with a leaf spring driven rear axle or as a front wheel drive unit it probably equips more cars in the world than any alternative concept. 

 The strut itself is the load bearing member of the assembly, with the spring and damper merely performing their duty as opposed to holding the car up. The steering is either connected to the lower shock absorber housing or to an arm from the front or back of the spindle. When your steer it physically twists the shock absorber housing (and the spring) to turn the wheel.

Whilst Mac Struts underpin many cars makers obvious don't want to pay Ford royalties, which is probably as much a reason as any other that there are now so many variation of the Basic Strut around.

Porsche, Audi, Vauxhall and many others have variations on the Mac Strut in use.