Bret Voelkel of Air Ride Technologies
Air springs are to suspension systems what vacuum-secondary carbs are to engines. Catch a glimpse of vacuum-secondaries under the hood of a hot rod and you'll automatically assume the motor's a turd. Real men want full throttle right now, baby, and dig carbs that hit hard! Never mind the fact that vacuum-secondary carbs can easily make as much peak horsepower as their similarly sized mechanical-secondary counterparts without sacrificing streetability. Likewise, witnessing a car that can alter its ride height at will elicits a similar knee-jerk response. Air suspension is for poseurs, not racers, so it has no place in your musclecar, right? Not if Air Ride Technologies has a say in the matter.
The company has developed a habit of making converts out of skeptics. Not just any skeptics, but pros who happen to be among the best road racers in the country. Air Ride enlists big-time racers such as Boris Said and Scott Pruett-two guys who race alongside the likes of Jeff Gordon and Tony Stewart-to test its products, and the feedback from the harshest critics around has been overwhelmingly positive. Common sense says that if it impresses them, it will probably impress you too. So how does it work, what are its benefits, how do you tune them, and how hard are they to install? We talked with Bret Voelkel to find out, and we quizzed him on other assorted suspension design topics as well.
Installation Tips
Although it takes the better part of a weekend, installing an air suspension is rather straight-forward. The only special tools you may need are an electric saw and a welder, and a digital angle finder will assist in setting up the pinion angle. "As with any customization, take your time by measuring three times and cutting once," Bret explains. "If you run into a problem or a question, please give us a call, since that is why you bought the stuff from us in the first place. I always advise customers to call a potential manufacturer with some trial questions before buying to determine the level of service they can expect after the sale. We have our installation instructions on our Web site so the customer can get a good idea of what he is in for before buying."
Spring Rates
Whether a progressive-rate spring or a linear-rate spring is better for hard-core cornering is much debated, but there is a time and place for each. According to Bret, the only argument against using a progressive spring rate would come from the potential tuning headaches it creates for novices. "A progressive spring rate is just one more tuning variable to throw into the mix when it comes to overall suspension tuning, but if you have an adjustable suspension and the know-how, then that variable is easily manageable," he explains. When it comes to air springs, they can be made to be perfectly linear or extremely progressive. Air Ride typically uses double-convoluted air springs in the front suspension since it's highly leveraged. "This is because the front wheel always travels faster and longer than the air spring and shock, so we want the air spring to gain spring rate much quicker to properly control the oscillations of the vehicle. In the rear, we typically use a sleeve-style air spring with a nearly linear spring rate. Since the rear air spring is more of a direct load application that moves at the same rate as the axle and wheels, it needs more travel and a softer spring rate throughout its travel."
Drag Racing
For those with eclectic tastes, an unfortunate byproduct of a tight chassis that handles well is compromised grip at the dragstrip. With the extreme adjustability of an air suspension, however, you can have the best of both worlds. "Just like any other form of racing, setting up an air-suspended car for drag racing isn't much different from setting up a traditional suspension," says Bret. "I am not a drag racing expert, but in general, we try to set the car up as loose as possible without getting into wheelhop. Loosen the extension valving on the rear to allow the rear suspension to lift the car and plant its tires. Also, loosen the front extension valving to allow the front end to come up and transfer the weight to the rear while keeping in mind that some cars like a bit more preload in the right rear spring to plant that tire better."