[DryStout]

I thought this was an intriguing quote from the following link. See below.

http://www.maximum-cars.com/Cars/Car.php?carnumber=624


[Working on a clean sheet of paper, Mustang’s engineering team could have selected any type of setup at the rear, including an independent suspension. So why choose a solid rear axle? The answer lies in Mustang’s position as America’s muscle car.

"We talked to a lot of Mustang owners and racers when we were developing this program," says Thai-Tang. "They are a very passionate group, and a lot of them told us – very strongly – that the all-new Mustang must have a solid rear axle because of its combination of performance and modification flexibility." ]

Who would have thought a solid rear would be chosen over an IRS.

[sgarnett]

Drag racers may well make up 90% of the performance-minded buyers.

However, as a product development engineer myself, I can tell you that there's no such thing as a truly clean sheet and the engineers are NEVER free to simply choose what will work best.

Besides ride, reliability, and drag racing, other influences include tooling costs, material costs, manufacturing costs, assembly costs, component and assembly commonality between models and platforms, warranty costs (related to but not the same as reliability).