by Tommy Lee Byrd and Kyle Tucker
(taken from Detroit Speed's How to Build a Pro Touring Car)
Before I get into individual parts of the front suspension of most muscle cars, I’ll address the first question that most people have, and that is ride height. Muscle cars stood tall from the factory, so it’s pretty common for folks to lower the ride height, even if they don’t plan to go fast and corner hard. Just like any other automotive modification, there is a right way and a wrong way to lower the front suspension. First of all, put the torch away; you do not need it.
The absolute worst way to lower the front suspension is by heating the coil springs with a torch. Sure, this makes quick work of putting your car in the weeds, but it completely ruins the springs by taking the tension out of the metal. As you can see, excessive heat has collapsed this coil spring.
Using a torch to heat the coil spring to the point of collapsing is the absolute wrong way to lower a car. Sure, it lowers the car, and you can do it without turning a single wrench, but it’s just downright dangerous. It weakens the coil spring, which ruins any car’s handling abilities. Fortunately, there is another cheap, at-home solution to lowering the ride height that actually works. Cutting the coil springs is an accepted way to lower a car because, in most cases, it increases the spring rate. This stiffens the front suspension, helping to resist body roll under hard-cornering situations.
With the coil springs out of the car, you can see that they were no longer doing their job as intended. Heated springs create a very spongy ride characteristic, which obviously isn’t ideal for hard cornering. Lowering springs is the correct way to lower the front suspension without sacrificing ride quality or performance.
Another way to lower the front suspension is with drop spindles. These modified spindles are designed to lower the ride height 2 inches without any negative effects on the suspension geometry. This is accomplished by moving the spindle higher on the upright to bring the car lower to the ground.
To perform this modification you must remove the springs, and use a cut-off wheel (or any metal-cutting device) to remove a portion of the coil spring. It’s common to see enthusiasts cut a “round” out of the springs, which means removing the first full coil in the spring. This usually equates to about 3 inches, but it varies based on the make and model of your car or truck. The most desirable way to lower the front suspension on a car from the muscle car era is to use a pair of drop coil springs. Many options are available for various ride heights and spring rates, allowing you to perfectly dial in the stance and handling performance. Another great method involves swapping to a drop spindle. These aftermarket spindles lower the suspension without messing with the suspension alignment, although some aftermarket spindles feature a different overall height to help with suspension geometry. Using a drop spindle with an original coil spring doesn’t improve handling, because of poor spring rates and metal fatigue. Drop springs and drop spindles are affordable options that work well on mildly modified Pro Touring builds. High-end builds generally feature an aluminum-bodied coil-over shock design, which provides vast adjustability.