Whether its for a show car or a canyon carver, a stock-height suspension just doesnt have the right lookand certainly doesnt perform as wellas a car that has been dropped a couple of inches all the way around. But why would you ever want to lower your car in the first place?
There are several rules of thumb pertaining to a lowered vehicle. Obviously, if your car is a true show car, general consensus says a slightly lowered ride stance combined with the right wheels and tires gives the car a distinctive look. For a canyon carver, the most obvious reason is to lower the cars center of gravity as it lumbers through the turns. However, dropping the car doesnt necessarily mean it will handle turns any better than before. It just means the car is lower. Follow along as we demonstrate several ways to lower your car, both the right way and the ultra-cheap way. (Notice we didnt say the wrong way.) We will tell you how thousands of cars have been dropped, most of the time incorrectly, and the numerous ways to lower your car correctly, maintaining the proper suspension geometry and creating a better-handling machine.
Spring rate applies to all types of coil and leaf springs. Spring rate is defined by how much weight is required to deflect the spring one inch at a time. Usually measured in pounds per inch but often given only in pounds, it describes the rate at which the spring compresses and then returns to its normal configuration. Do not confuse spring rate with load rate, which is the amount the spring is designed to carry at a certain height. The width of the spring, the diameter of the wire, and the pitch between the coils will also determine spring rate. The thicker the wire, the higher the spring rate. The higher the pitch, the higher the rate as well.
Cutting a stock spring will also increase its rate by roughly 10 percent for each coil removed. Two coils equals a 20-percent increase in spring rate. Despite a higher spring rate from cut coils, the cars ride qualities will be significantly affected, and the suspension may bottom out because so few coils remain. So you may have a cool-looking ride stance, but now there is little or no suspension travel left to control ride harshness.
Dropping The Front
Lowering the front end of your car can breathe new life into a stale project. Combined with the right wheel/ tire combo, the new look is sure to garner lots of oohs and aahs. The old way to lower a coil-sprung front end was to jack the car up, fire up a welding torch, and heat the springs until the temperament was relieved. This made the springs sag and thus lowered the front end. The bad thing about this method, besides that it renders the coil spring virtually worthless and forces the shock absorber to do all of the road dampening, is that the car often ends up with an uneven ride height, because one spring may sag more than another.
A more acceptable, inexpensive method is to cut the coil spring. This requires complete removal of the spring from between the upper and lower control arms.
If you have ever rebuilt a front suspension, then you already know the dangers of removing a coil spring if done improperly. To cut the spring, you can use a diamond-tipped hacksaw blade, but that will take some time. A better way is to use an abrasive, air-powered cut-off wheel or a bench-mounted chop saw. A good rule of thumb when you cut a spring is to work in ¼-coil increments at a time. With half a coil removed, the car should be dropped roughly 1 inch overall. A problem with cutting the spring ¼ coil at a time, though, is that achieving the correct drop will require you to install both springs back into the car and allow it to settle before you can figure out if it is the correct amount of suspension drop.
Dropped Spindles Vs. Short Springs
A popular product that has evolved from the sport-truck world is the dropped spindle, which moves the spindle higher in the forging than it is in a stock unit. When a dropped spindle is bolted in the place of its stock counterpart, the body and frame are effectively lowered over the wheels, giving the car a lower stance. Most dropped-spindle manufacturers can drop your stock front suspension approximately 2 inches with the simple addition of a dropped spindle, without cutting or replacing the coil spring. With a dropped spindle you are not changing the ride characteristics at all, because the spring rate hasnt been altered. The car should handle slightly better than stock because the center of gravity has been lowered, but the car will still not be a true canyon carver without the addition of a set of higher-rated coil springs to increase roll stiffness.
A problem with a dropped spindle is maintaining the proper suspension geometry and the proper clearance between the lower control arm and the wheel when it is turned to a full-lock position. A dropped spindle, when installed properly, tucks the wheel up higher in the wheel well and physically pushes it out closer to the fender lip to help maintain correct geometry. As long as the proper wheel/tire combination is used there shouldnt be a problem. This means getting the right wheel with the right offset and proper tire section width.
A shorter coil spring works the same as a stock coil spring. Both are designed to control ride qualities. Often a shorter spring will come with the same amount of coils in it as a stock spring, but its wound more tightly, which effectively makes the spring shorter. Most shorter coil springs are variable-rate, which means the first couple of coils are very tightly wound, while the rest are more loosely wound. Generally, the tighter the windings, the softer the spring rate. This means that the first few inches of travel will be fairly soft, for around-town driving, but when compressed further as your driving style becomes more aggressive, the spring rate will increase. So, for example, on a stock coil spring, if it takes 200 pounds to deflect the first inch and another 200 pounds to deflect the second (400 pounds total), on a dropped spring with a variable rate, the first inch of deflection may take the same 200 pounds, but the second inch of deflection may take 250 pounds or more.
Getting Low In The Rear
Early Camaros and Novas comprise the leaf spring brigade. Leaf springs are bunched together in a pack with the leafs going from short to long and are mounted below the axles. In addition to locating the axle both fore and aft in addition to side to side, springs also support the weight of the vehicle. The center of the leaf spring is attached to the axle via long U-bolts and a backing plate, while bolt clips are often used to prevent the leaves from fanning apart. The spring rate is based on width and thickness. The most common leaf spring is the semi-elliptic. On the ends of both semi-elliptic springs, there are eyes which are used to mount the spring in its perch. Most semi-elliptic springs come either positively or negatively arched depending upon the cars ride characteristics.
To lower a semi-elliptic spring, simply replace it with a de-arched spring, which changes the overall arch or bend in the spring. This can be done by placing the spring in a press and bending the spring at the arch to the desired height. However, it is advised that you let a spring manufacturer do the bending, because he will know how much bend is acceptable. Eaton Spring offers replacement de-arched springs for a variety of makes and models that will safely and effectively lower your cars ride height.
Another way to lower a leaf-spring sprung rear is with the simple addition of a set of lowering blocks. Placed between the axle and the lower spring pad, the blocks cause the axle to be raised up from the arc of the leaf, thus putting the rearend housing closer to the frame. A 2-inch lowering block is acceptableanything more and you may experience driveline and pinion-angle problems.
The Grand Slam
If you really want the lowest car in the neighborhood, extreme measures are in order, entailing serious frame modifications and some floorboard re-shaping as well as frame reconstruction. One of the oldest methods for the severe rear ride stance is Z-ing or C-notching the rear frame rails so the axle has room to travel. Usually, both methods require floorboard surgery because of the new frame kick-up. Unless you are an expert welder and know how to set the proper pinion and driveline angles and replace the floor sheetmetal, this should probably be left to the professionals.
Another way to lower the car that has caught on with show-car enthusiasts is an adjustable air-ride kit. A set of air bags replaces the coil spring and, in some instances, the rear leaf springs. Air bellows are fitted in place of the original coil spring and, once filled with air, will raise the car to the desired height. Deflate the air bellows, and the car will be a ground-hugger. Many companies offer full air-ride kits that can be bolted into place at home with basic hand tools. The key thing to keep in mind is that pinion angle should be set at the desired driving-height stance. While driving down the road, the vehicles ride height should not be altered, because it will adversely affect pinion and driveline angles.
Whether you choose to lower your car for aesthetics, with little concern for ride and handling characteristics, or you want to transform your land yacht into a canyon carver, have a plan before starting. There shouldnt be any reason that your lowered ride should suffer from poor ride characteristics, unless that was your intention from the beginning but odds are it wasnt. Take advantage of the plethora of parts now available to get your car in the weeds with just the right look and desired purpose. Combine good looks and true functionality, and you have the best of both worlds.