09 Challenger FAQ
09+ Challenger Technical Page
Which spring is right for my Challenger?
Hotchkis Sport Suspension has spent numerous hours developing a system for the 09 Challenger that has the perfect blend of High Performance, and a comfortable ride. Based on consumer demand we have developed spring options for the Challenger owner in regards to the desired amount of drop.
SRT owners can enjoy a comfortable ride, and a moderately lowered stance by using our spring kit #19107. This kit lowers the SRT 5/8″ Front and 1″ Rear for a subtle drop. The Challenger SRT below is equipped with a Hotchkis TVS consisting of 19107 Sport Coil Springs, and 22107 Sway Bars.
RT owners have a choice of drops and can enjoy a comfortable ride, and a moderately lowered stance by using our spring kit #19108. This kit lowers the RT 1 7/16″ Front and 11/16″ Rear for a subtle drop. The Challenger RT below is equipped with a Hotchkis TVS consisting of 19108 Sport Coil Springs, and 22107 Sway Bars.
For those RT owners looking for a more aggressive drop, the 19107 springs from the SRT can be used for a 2″ drop all the way around. The Challenger RT below is equipped with the 19107 Sport Coil Springs and 22107 Sway Bars.
NIVOMAT Equipped Cars
Owners with cars that are equipped with the NIVOMAT self leveling shock absorbers are not able to lower the vehicle without a shock change. We have successfully installed the Bilstein shocks on these cars with great results.
More information on Nivomat courtesy of Edmunds Inside Line
More information on Nivomat courtesy of Edmunds Inside Line
Alignment
Many new Challenger owners have asked questions regarding alignment after lowering their vehicles as many alignment shops tell them the vehicle is “out of spec.” Obviously vehicles that have been lowered will have alignments that vary from the original settings, but what is acceptable?
From our experience tuning suspension systems, vehicles will benefit by running negative camber in the front which allows more tire contact patch during cornering. Owners are sometimes concerned about tire wear when running negative camber. The truth to the matter is, camber (unless excessive -2.5″ or greater) plays less a role in tire wear than does toe. Often the cause of uneven tire wear is blamed on camber when the true problem is toe. By properly aligning the vehicle after lowering and setting the toe settings to 1/16 front and 3/16″ rear total toe in, tire wear can be minimized.
After installing our 19108 Sport Coils Springs (Front: 1-7/16″ Rear: 11/16″ Drop) on a 09 RT we were able to achieve the following alignment specs without the use of any aftermarket alignment products.
Front Camber -0.8°
Rear Camber -1°
Front Camber -0.8°
Rear Camber -1°
These camber settings are perfectly acceptable for daily driving and will not adversely affect tire wear. Toe was set to front 1/16” total toe in and the rear 3/16” total toe in. These are the settings you should be using for Toe.
The SRT8 models experience slightly different alignment specs as well as RT models using the 19107 springs. We have seen -1.3° in front and -1.8° at these lower heights. While the front is still within acceptable range, the rear could benefit from some form of aftermarket alignment kits. Optimum rear camber settings would be -1 to -1.5°
The key to properly aligning these vehicles is:
1. Make sure the rear sub frame is aligned and installed correctly after changing the rear springs, a mis-aligned sub frame will create alignment issues.
2. Use an experienced alignment shop. Just because someone does alignments, doesn’t necessarily mean they know what they are doing. Performance cars with aftermarket parts require special needs, and experience.
1. Make sure the rear sub frame is aligned and installed correctly after changing the rear springs, a mis-aligned sub frame will create alignment issues.
2. Use an experienced alignment shop. Just because someone does alignments, doesn’t necessarily mean they know what they are doing. Performance cars with aftermarket parts require special needs, and experience.
Bump Steer
Bump steer was a topic of conversation we found in many internet threads, so we measured a 09 R/T to determine the amount of Bump Steer, or toe change the vehicle experiences. These are the numbers we recorded for front bump steer:
The toe change during bump travel is very minimal, showing only a 1/16” of total toe change within 3 inches of bump travel. 1/16” of a inch is so minimal the driver wouldn’t even be able to feel it. Compare that to a stock 70′ Challenger with over 3/8” of an inch of change. From these numbers, it is not necessary to purchase or install any aftermarket bump steer kits on the 09 Challenger at these lowered heights.
cWant to learn more about Bump Steer? The video below explains how we measure bump steer.
What will upgrading my sway bars do?
Sway bars are the most significant upgrade many Challenger owners will make in regards to improving the vehicles handling. Upgraded sway bars reduce body roll, and improve cornering and handling performance without adversly affecting ride quality. Hotchkis Sport Suspension develops sway bars through vehicle testing. While many companies produce sway bars that are merely larger than stock using engineering formulas, we take the vehicle to the track and use 600 FT Slalom data to help us determine the best handling balance for the particular vehicle. This testing allows us to design the best sway bars on the market and ensure our customers the ultimate performance possible.
I have a SRT, how can your sway bars be any better?
There is always room for improvement. From the factory vehicles are tuned to offer a level of performance that sells cars to the masses. Aftermarket products exist for those consumers that want to take their production vehicle to the next level of performance.
Below is a chart of factory sway bar sizes and equivilent Hotchkis upgrades.
| Model | Stock Front | Stock Rear | Hotchkis Front | Hotchkis Rear | Hotchkis % Change |
|---|---|---|---|---|---|
| Magnum | 30MM Solid | 15MM Solid | 35MM Tubular | 19MM Tubular | +30% F, +150% R |
| 300C/SRT8 | 27MM Solid | 15MM Solid | 35MM Tubular | 1MM Tubular | +100%F,+150%R |
| Charger | 27MM Solid | 15MM Solid | 35MM Solid | 19MM Tubular | +100%F,+150%R |
| Charger SRT | 27MM Solid | 15MM Solid | 35MM Solid | 19MM Tubular | +100%F,+150%R |
| Challenger | 30MM Solid | 15MM Solid | 38MM Solid | 19MM Tubular | +100%F,+150%R |
| Challenger SRT | 30MM Solid | 15MM Solid | 38MM Solid | 19MM Tubular | +100%F,+150%R |
OTHER FREQUENTLY ASKED QUESTIONS
Q: Does lowering the suspension on my Challenger put extra stress or strain on my suspension parts? I have heard I should buy a bump steer kit to aleviate stress.
Answer: At the lowered ride heights, the vehicles static ride has been changed from factory, but the arc of travel the suspension follows remains the same, therefore the steering components and ball joints will see the same range of motion as designed from the factory. The aftermarket bump-steer kits can allow the owner to change the relative location of the steering arm, in relation to the spindle, but the arc of travel the suspension follows will always remain constant. The rod ends that are typically used in steering upgrades offer a superior level of steering feel over factory tie rods, and may offer better articulation and adjustment, but there can be a downside to that as well. Rod ends typically have a lower service life than factory tie rods, and often become noisy over time. We use rod end steering components on other platforms, so we are not here to say they do not have their place in performance applications. Drivers just need to be aware that when used on daily driven vehicles, additional noise may be present.