Freedom of Movement

Install a Bolt-On Independent Rear Suspension for Early Camaros and Firebirds

- Steven Rupp

Our classics are great, but let’s be honest, their suspension systems were designed over half a century ago, and since then technology has come a long way. Today’s handling has spoiled us, and we really notice how deficient the factory handling is when we compare it to our modern daily drivers. This is where bolt-on suspension parts come into play, in this case, an independent rear suspension (IRS) system.

The reason that nearly all modern cars use an IRS is that it’s simply better when compared to a live axle in regard to handling and road manners. In terms of ride comfort and overall driving, it’s superior in dealing with turns and uneven road surfaces. A live axle (sometimes referred to as a solid rear axle or SRA) means that whatever one wheel does affects the other wheel. So, when one wheel hits a pothole or dip in the road, then the other wheel is forced up, resulting in less downward force and hence less traction. Also, with an SRA there’s no way to make suspension adjustments such as changes to the camber (aside from some high-end track-prepped SRA floater kits). The ability of the IRS systems to let the wheels work independently of each other (hence the name) along with the additional suspension tuning that’s possible, makes the IRS a hard system to beat. One downside is that an IRS will have greater unsprung weight, and by necessity will be far more complex, compared to an SRA setup. If done right an IRS system will outperform an SRA in all handling and road driving situations, though an SRA system will win when it comes to drag racing.