Published on April 6th, 2015 | by Daniel Sherman Fernandez1
Is multi-link rear suspension better?
Over the last few years, it seems that the average car consumer has wizened up when it comes to technical specifications. Besides the standard safety features like Electronic Stability Control and an array of airbags, people are also looking at whether a car comes with all-round disc brakes, or in this case: multi-link rear suspension.
We know that on higher end cars, multi-link rear suspension is the norm. Quite nearly all of the D-segment cars are multi-link equipped, and every continental car comes with a multi-link rear setup. The alternative these days is torsion beam (or twist beam), which is usually met with disdain by both average consumers and enthusiasts alike.
Why the hate? In the good old days when development budgets were seemingly infinite, economies were strong, and car companies were far more prosperous, multi-link was common across the range. Torsion beams were reserved for only the cheapest, smallest cars- being both cheap to produce and engineer, as well as more compact in nature so they didn’t sacrifice boot space.
But as the times changed and we hit recession after recession, companies learned to cut back. They learned to make their operations leaner, to tighten their belt buckles, and to produce cars that were more budget friendly. Honda went from having double-wishbones all round, to having double-wishbones at the front, and eventually dropping wishbones entirely.
Soon torsion beams began to spread throughout the entry-level market. For all intents and purposes, people viewed this as a cop out for car companies to cut back on costs at the expense of the consumer. And yet these cars handled reasonably well, even with their torsion beam rear setups. The truth is that it is very difficult to differentiate between torsion beams and multi-link throughout the vast majority of on-road situations.
The key is in the difference between multi-link and torsion beam rear suspension setups. Multi-link setups allow independent movements of the wheels on either side, while torsion beam ties the wheels together to a certain degree. That is to say that with multi-link, a wheel can move up and down without moving the other wheel. With a torsion beam, both wheels will rise and drop almost simultaneously. But modern torsion beam engineering allows for a certain degree of flexibility between the wheels, which provides pliancy and comfort. Of course this is a simplified explanation- we’ll expand on this on a later article.
But let’s not forget that some of the best handling front-wheel drive cars on the market these days use a torsion beam rear suspension. The new Civic Type-R hatcback, the Megane RS265, and the Fiesta ST are all champions of the torsion beam pedigree. The truth is that with enough engineering effort, it is possible to make a torsion beam car handle just as well as a multi-link. But whether every aspect is quite nearly as good- that’s something we’ll touch on next time.