We enjoy driving our 2009 Dodge Challenger, as it is arguably one of the most well-rounded vehicles ever produced by the Chrysler Corporation. With Hemi power, great braking, and independent rear suspension the new Challenger does everything well, but of course we wanted our R/T model to perform better than it does in stock form. To enhance our car's performance, we've already installed a ProCharger supercharger and aftermarket exhaust, as well as Wilwood disc brakes with six-piston front calipers, four-piston rear calipers, and large diameter rotors to get our Challenger stopping in shorter distances. To improve our car's handling, we installed Eibach front and rear sport suspension featuring larger diameter sway bars, re-valved shocks, and stiffer front and rear coil springs with a lowered ride height. We also installed a bumpsteer kit from Razor's Edge Motorsports. There's one area of the suspension found in late model Mopars, the factory rubber bushings, that limits how well these cars handle, so we decided to replace the stock suspension bushings in our Challenger for enhanced handling performance.
1. Energy Suspension has more than 20 years experience manufacturing polyurethane suspensi
When any car is manufactured, there are always compromises in terms of performance, ride quality, and costs. The suspension of the new Chrysler products is no exception, as they install the best components they can, to offer good handling and ride, while still being able to sell the car at a competitive price. We've already replaced some of our Challenger's suspension components like the shocks, springs, and sway bars, and have enjoyed better handling and braking thanks to these changes, but to eliminate the flex and body roll that the rubber bushings allow, we felt that they had to go. Every car, including our Challenger, has rubber components in the suspension, which are intended to isolate the individual components from the rest of the car, preventing vibrations from disturbing the car's occupants. The Challenger, as well as the new Chargers and 300s, use rubber bushings throughout the front and rear suspension, even where the rear suspension cradle is attached to the car's subframe.
The problem with rubber bushings is that, while they do a good job of insulating the car from road noise and vibrations, they also allow a considerable amount of suspension flex, which is counterproductive to good handling, acceleration, and braking. There are rubber bushings throughout the late model Challenger, both in the front and rear control arms, trailing arms, and shock mounts, and the combined affect that these bushings can have during aggressive driving is substantial. Rubber bushings allow a great amount of flex, especially when the car is cornering, and can prevent the tires from making maximum contact with the pavement as well as altering the alignment of the front and rear wheels. In the front, this issue is amplified by the rubber bushings holding the rack and pinion in place, and in the back, the entire independent rear suspension cradle is held in place by rubber bushings.
2. We wanted to quantify the difference these suspension components would make, so we took
For maximum performance, the factory suspension bushings should be replaced with components that flex less than rubber. In all-out racing applications, certain bushings are replaced with solid components, but in street cars or street/strip applications, the bushings still need to isolate the vibrations from the car's cabin. Energy Suspension is known for their line of high-performance suspension components for classic Mopars, and now offers polyurethane front and rear suspension parts for late model Dodge and Chrysler products.
Polyurethane is an advanced product that flexes far less than rubber, but still allows a certain amount of isolation between the car's chassis components and the car itself. Energy Suspension has more than twenty years of experience with polyurethane, and their Hyper-Flex performance polyurethane is a proprietary, technically advanced formula that has earned them nine U.S. patents. Unlike rubber, Hyper-Flex performance polyurethane components don't compress from weight or road forces, and won't rot or deteriorate due to exposure to oil, chemicals, or road salt. Hyper-Flex components are a free-floating, non-binding design, and Energy Suspension track tests all of their products before bringing them to market. The Energy Suspension Hyper-Flex components are available in red or black, both offering the same basic chemical polyurethane formula, with graphite added to some of the black bushings for additional lubrication. For our Challenger, we chose a full set of front and rear bushings in red, and decided to test our car on the track to determine how much of a difference these bushings make. To establish a performance baseline for our Challenger, we took the car to Auto-Plus Raceway in Gainesville, Florida, for some timed laps around their road course. With the factory rubber bushings in our Challenger's suspension, our car turned lap times of 1:16.6 and 1:16.5 on its best two laps. With our baseline established, we took the car to Inline Performance Specialists in nearby Bushnell, Florida, to install our Energy Suspension Hyper-Flex polyurethane bushings.
3. With our baseline lap times established, we took our Challenger over to inline perform
4. There are several ways to remove the factory rubber bushings, including
using a propan
5. The Hyper-Flex polyurethane bushings don't just perform better than the factory rubber