Muscle Mustangs & Fast FordsHow To Chassis Suspension
Air Ride Technologies' CoolRide Air Suspension System - Slam Dunk
We've got Ice Box sitting low and riding nice with Air Ride Technologies' CoolRide air suspension system.
How Low can you go? That's been a question Mustang owners have asked for a long time. Low is cool, as long as your Pony doesn't end up riding like a bucking bronco. Fact is, virtually all late-model Mustangs can stand to be dropped a bit as they suffer from a ride height that's just not aesthetically pleasing. Dropping your Stang gives it a meaner look and lowers the center of gravity, which can also improve handling. But all too often, owners slam the car to the ground by cutting the springs or by installing short, overly stiff ones. In doing so, they end up with a harsh ride, terrible handling, and poor driveability.
Still, Mustang owners want to get down, and one cool way to get 'er low is with an air suspension like the ones offered by Air Ride Technologies of Jasper, Indiana.
Air suspensions are nothing new. Most of today's product goods transported by truck ride on air-air springs, to be more accurate. Additionally, many luxury cars, including some trucks and SUVs, ride on air suspensions and have done so for decades. With the latest from Air Ride, you can get your Stang riding on air, too.
To find out more about this, we ordered a kit for Ice Box, our 10-second Mustang GT project Pony. Not so long ago, we added Eibach's coilover Pro Kit to the steed, but the suspension was not properly matched to the power and the other components we had installed, thus, it never reached its potential. Oh, it accelerates like a missile, but its cornering could be improved upon. The problem is that the rear springs were too soft when compared to the front coils, and this made the back of the car seem like it was disconnected from the front. In addition, we had huge antiroll bars (also from Eibach), and the combo just wasn't working for us.
To improve our project Mustang, Air Ride Technologies supplied us with its CoolRide front air springs that replace the coil springs but retain the struts, and its Shockwave rear air springs that incorporate adjustable shocks into one component. The kit also includes a 3-gallon air tank, a sealed air compressor, a RidePro e control panel, sending units, lines, and all the necessary wiring and hardware for a clean installation. It also comes with an easy-to-use, four-way controller that lets you adjust each of the four springs individually, right from the driver seat. Together, the package offers full control of the ride height and ride quality.
With parts in hand, we teamed up with Dan Ryder of Danny's Pro Performance in Cliffwood Beach, New Jersey. We spent a day and a half installing the hard parts and hooking up the lines and electronics. After installation, our hope was that the Mustang would have better overall balance and improved compliance, something it lacked with the current setup. The install went well, but the instructions could have provided more detail.
Some may be wondering if airbag or air springs are potentially dangerous. Not so, says Bret Voelkel, president of Air Ride Technologies. "Our airbags are made to our specs by Firestone, the world's largest air spring manufacturer. They are used on large semi-trucks, off-road equipment, luxury cars, and also in industrial machinery, conveyer systems, and load stabilizers. We recently sold an air spring to replace a unit that had been in service for 17 years. It was replaced because the end plate had rusted out. Failure can happen, but it's extremely rare. We require the vehicle to have at least 2 inches of ground clearance when the air spring is fully deflated."
And with that myth quelled, we can move on to the performance of such a system.
Associate Editor Steve Baur has sampled a few Air Ride-equipped vehicles in the past, and he had this to say in our March '05 issue: "Air Ride Technologies is probably known best for dropping classic and musclecars, and we got to sample a few of those. Our favorite was the '69 Mustang that belonged to Voelkel. His mean-looking musclecar sported a 351 with a ProCharger, a Tremec five-speed trans, and of course, an air suspension.
"The vintage Pony was the first car we sampled out on the track, and not having had a previous opportunity to push an older Mustang in the turns like we planned to there, we didn't know what to expect. If you weren't looking at the dash, though, you never would have noticed you were in a 34-year-old car. It handled just as good as the current models. Cornering was flat, firm, and without a lot of drama, which allowed me to focus on car control and finding the next apex."
He continued, "Over the course of the day, we were able to make numerous road course laps, as well as run slalom and 60-0 braking tests. The thing we noticed most about the air suspension was how flat the cars (and trucks) cornered. The suspension's obligatory drop in ride height lowered the center of gravity, which helped greatly, and rebound and damping were extremely smooth but firm. The vehicles had a cloud-like ride, but were unwavering when it came to turning. After the event, we confessed to being born again. The air suspensions really do work in a high performance/racing application."
Voelkel added, "Changing air pressure and shock valving alters spring rate and how soft or firm the car will ride. There's adjustability to optimize street and track driving, and you can get the best of both worlds because you can change the rates so easily. If you have enough time and patience, you can tune a coil-spring or leaf-spring suspension, but it takes a lot more work to do it. The fact that you can lower the car and improve the looks is a happy coincidence."
While on-track performance is important, many owners will be concerned with the characteristics of such a suspension on the street, and rightfully so, because that's where most Mustangs spend their time. So, after making all the connections, we put Ice Box to the test.
Naturally, we got the anticipated drop, and what a drop it was. With the air dumped from the system, our Mustang sat on the ground-OK, about 11/44 inch off it. After charging the springs with air (which takes only about 2 seconds if the tank is full), our Mustang was ready to be driven. We started out with about 100 psi in the bags, which proved to be far too stiff and put the car way too high.
Lowering the pressure instantly improved handling and ride quality. Prior to the install, the Mustang would pound over imperfections in the roadway; it now absorbs the bumps without any drama. There is also much more control and a feeling that the front and rear are connected.
We questioned the folks at Air Ride about picking the best struts and antiroll bars, and they told us that any parts will work. But we know better. Just like any suspension, we'll have to test to see which is quickest on the track and the smoothest on the street. However, before we make any changes, or run any hot laps, we're going to get the Stang's front end aligned.
"Before setting the front-end alignment, drive the car and find the most suitable pressures and ride height," Voelkel says. "Then have the car aligned using that ride height." He also says the vehicle can be raised or lowered a small amount without upsetting the alignment too much.
After a few miles, we determined it rode best with 80-85 psi in the front and roughly 65-75 psi in the rear and with the valving in the rear shocks set on soft, or about three clicks from full loose. This produced a comfortable ride, even with the meaty 18-inch Nitto tires, without any tire rub and with good compliance over rough portions of roadway. We were also impressed at how low we could get the car while maintaining good ride quality. Even with the soft setup, the Mustang cornered well. It was hard to tell such an exotic suspension lie underneath, but it rode as nicely as some of the best coil-spring suspensions we've tested.
Nevertheless, it was strange to dump air and lower the car to soften the ride. Normally, you would want taller, softer springs to give a smoother ride. But lowering the car softened the spring rates and smoothed the ride, until we went too low and caused tire rub. As for straight-line acceleration, there is no apparent advantage to this type of system.
Overall, we found the system to be moderately difficult to install, but easy to use and adjust. If we had a gripe, it was that the directions could have been more detailed, and the tech line could have offered better recommendations for matching the springs to a proven combination of struts and antiroll bars. When contacted, the guy we spoke to stated "whatever you had should be fine." Not what you want to hear after you've spent thousands on new springs and rear shocks.
With the project completed, we learned it's best to adjust the springs when the car is sitting on flat ground, not on an incline or while the vehicle is moving. And as with any new springs, the Air Ride air springs may require that you install new struts and antiroll bars to maximize ride and handling both on the street and on the track. Next we'll get an alignment and then it's off to the track.