An Extensive Look At Suspension
The 1913 "Little Six" (marketed along side the Chevrolet Six by the Republic Motor Company) is a perfect example of early suspension technology. Up front was the state-of-the-art (for the time) semi-elliptic front spring setup and in the rear a kind of unique design called 3/4-platform suspension. As you can see, the 3/4 platform design used a front-hinged frame to support the rearend with a transverse leaf attached at one end (making up the third quarter) to provide flexibility.
From what I understand, back in mid-1904 the experiences of a young man named William Brush helped to initiate advances in automobile suspension systems that led them well on their way to becoming what they are today. His discovery, or rather its prelude, was the result of a mishap while hot roddin' in his brother's car. Brush was rolling along way too fast for the inadequate unpaved roads of the day and hit a turn at around 30 mph.
Midway through the turn the right front wheel skidded off the road into a rut and immediately began to shudder violently. The undulations of the jolted right front elliptic leaf spring sent shock waves across the solid I-beam axle causing the entire frontend of the car to shake furiously. Brush was unprepared for the situation and lost control, crashing through a fence and flipping over in a cow pasture.
Later that day, the youngster admitted what had happened to his older brother, Alanson, who was rightfully pissed off. Luckily for him Alanson was in the process of planning improvements to his creation, a car dubbed the "Brush Two-Seat Runabout," which finally hit the market in 1906. It featured a revolutionary (for the time) suspension system that incorporated two innovations which, up to this point, had never been used together--front coil springs and shock absorbers--all mounted to a flexible hardwood axle.
This is a production version of a Brush Runabout similar to the one mentioned earlier (though this is a four-seater).
Back then, some European carmakers had already been experimenting with coil springs, with Gottlieb Daimler in Germany being the leading advocate. However, most manufacturers stuck with leaf springs; they were less costly, and by simply adding or removing leaves or changing the shape from full elliptic to three-quarter or half elliptic, the spring could be made to support varying weights.
Leaf springs in one form or another have been used since the Romans suspended a two-wheeled cart on pliable wooden poles. The first steel spring put on a vehicle was a single flat plate installed on carriages by the French in the 18th century. Leaf springs as we know them today were invented by Obadiah Elliot back in London around 1804. He simply piled one steel plate on top of another, pinned them together and shackled each end to a carriage, which worked pretty well.
Here is a shot of yet another Brush. In this shot you can see both the wooden front axle and the pair of coil springs, this was high-tech handling technology back in the early 1900s.
Henry Ford's 1908 Model T Ford featured leaf springs with a novel twist, using only one spring at each axle, mounted transversely, instead of one at each wheel. Ford's adaptation of high-strength vanadium steel from a French racing car allowed him to save weight and cut costs in many areas of the Model T without compromising its durability.
The coil spring ain't no spring chicken, either. In fact, the first patent for such a spring (British Patent No. 792) was issued to a guy by the name of Tredwell in 1763. The main advantage of coil springs was that they did not have to be spread apart and lubricated at regular intervals to keep them from squeaking, as leaf springs did.
With the exception of a car here and there, independent coil spring front suspension remained in limbo for 25 years after the introduction of the aforementioned Brush Runabout. Then suddenly in 1934, GM, among others reintroduced coil spring front suspension, this time with each wheel sprung independently. In that year, most cars started using hydraulic shock absorbers and low-pressure tires, as well. The combination of solid front axles, shocks and balloon tires really aggravated frontend shimmy but the new practice of suspending each wheel individually lessened the effects of spring bounce. Soon after WW II, nearly all manufacturers switched to coil springs for the front wheels.
This is a zoomed in image of the 3/4 platform setup from the lead image. You can see how the parallel portions support the rearend housing pivoting on what look to be traditional front leaf-type mounts and the rear portion tied together with a multi-leaf spring
Buick became the first U.S. manufacturer to use rear coils back in '38. Manufacturers have vacillated between leaf and coil springs since then and it's been kind of a rule-of-thumb that large, heavy cars are equipped with leaf springs, while small light cars use coil springs.
Fast forwarding to the present day we see IFS as the norm and IRS as a bit more exotic. The musclecars we all know and love for the most part have received upgrades above and beyond what was offered as original equipment and through the balance of this issue we'll hopefully offer you some useful insight into both the theory and the availability of the systems and products that make your super Chevy a joy to drive.
Street Challenge Suspension Systems
Every year Air Ride Technologies hosts an annual event aptly named "The Street Challenge". This event was targeted to educate our dealers and the motorsports media about the hardcore performance benefits of a properly designed and tuned air suspension system. Now that the real world performance benefits of an air suspension have been exposed there has been intense customer interest in the specific equipment used at that event. In response to that interest Air Ride Technologies has put these top-notch components together into one complete suspension system appropriately named the "Street Challenge Package". These elite packages represent the finest air suspension equipment that is currently available for these vehicles including StrongArms, AirBars, Double adjustable Shockwaves, and Musclebar swaybars.
Street Challenge systems are intended for the serious hard-core performance enthusiasts who want a suspension system that is designed for their specific car and who will tolerate no compromise in either handling performance or ride quality. For more information about the Street Challenge packages for YOUR car, you can reach Air Ride Technologies by calling 812-482-2932 or visit them online at www.ridetech.com.