Chrysler 300 SRT8 Suspension Upgrade

SUMMIT RACING SUSPENSION UPGRADES FOR CHRYSLER 300'S, DODGE CHARGERS, CHALLENGERS AND DODGE MAGNUMS
Street stylin' with Summit Racing's KW Suspension upgrade and new Goodyear performance tires. No more driveway clearance problems while maintaining great performance handling characteristics. Read on to see how this great Summit upgrade can be applied to any Chrysler 300, Dodge Charger/Challenger or Dodge Magnum wagon. Ground clearance on this 300 SRT8 was raised 1-inch in the front and 1/2-inch in the rear to gain clearance over a severely humped driveway and other obstacles such as various facility entrances and exits without sacrificing performance.
Most late model performance cars are already equipped with a high performance suspension, but many downline versions are in need of suspension upgrades to improve their performance and agility on the road. As some enthusiasts have discovered, their cars are often too low to negotiate many driveways and entrances to shopping centers, gas stations and so on. We stumbled upon this problem when a reader moved to a new house with a significant hump at the entrance to the driveway. His Chrysler 300 SRT8 would drag the exhaust system and even the rocker panels no matter how slowly he eased it into the driveway.
A lower center of gravity is always desirable from a performance handling standpoint, but you can only take it so far before it becomes impractical for everyday use. If your car is a track only car its great, but if your vehicle does double duty that is heavily weighted toward everyday street driving, you need options. Using curb ramps to get into your driveway is one thing but that's not practical anywhere you go. Take a look at the comparison photos to the right and see if you don't agree. What's needed is an easily adjustable way to raise your car without resorting to the expense and complication of an air bag system.
You can't carry these heavy curb ramps everywhere you go, but you can carry these bolt-on adjustable coil-overs and therein lies the practical answer to your problems. Our Chrysler technical consultant Christine White recommended these high-quality KW Suspension components sold through Summit Racing. They have the range to raise your car enough to suit your needs. And they can easily be adjusted up or down for whatever ride height, stance or activity you desire.
Christine pointed out that many owners without driveway problems often raise their vehicles in the winter months and lower them in the summer for performance driving. And she noted that Summit Racing offers a full range of KW Suspension kits, not just for the Chrysler 300 SRT8, but also for Dodge Chargers and Challengers and Dodge Magnums. A lot of Mopar enthusiasts are turning to this solution and they are more than satisfied with quality of the parts and the utility and performance they offer. To check it out further, we ordered up a Summit Racing kit and installed it on the reader's SRT8. The object was to illustrate the installation process and to evaluate the performance and ride quality of the car as modified.
Here's the KW Suspension kit as it arrived from KW via Summit. It is very well packaged and includes a special tool kit for making the adjustments after you install it. KW has a U.S. presence, but they are a German manufacturer, hence the attention to detail and high quality. The installation instructions are in German and English so you won't have any trouble following them. 
The handsomely packaged tool kit contains two different spanner wrenches for adjusting the coil-overs up or down and a pair of adjuster keys used to facilitate rebound adjustments. It also contains a comprehensive instruction manual detailing how to make adjustments and level your vehicle. It comes in a hard plastic case so you can keep it with the car at all times.
UPGRADE TIME
The first step is to determine the existing ride height so you know how much you want to raise or lower your car. In this case the primary concern is driveway clearance. With the car parked on the offending driveway, measurements were taken at the front, center and rear of the rocker panel for future reference after the modifications are completed. Since we know the car hits the exhaust and rocker panels, we know we need to raise it approximately one inch.
We can check our work at ground level and in the driveway once the work is completed, but it is easier to work from a reference point on the fenders as it is all relative to the fixed ground point. The reverence point was 30 inches at the front and the rear wheel openings. and the car will be raised until those lines match 31 inches in the front and 30.5-inch at the rear.
With the car safely secured on jackstands and the wheels and tires  removed, it is an easy task to remove the factory struts. Compress the strut assembly with a floor jack, remove the upper mounting hardware and slowly lower the strut and spindle assemblies until the top comes free and you can unbolt the struts.
The suspension components are easy to install on a lift or on jackstands using basic hand tools. If using jackstands, the job will go smoother with the car at least fifteen inches off the ground. Remember that you are adjusting the ride height by changing the preload on the spring. This works well for almost all street applications. As shown in the accompanying chart, KW also makes kit variants that allow further adjustments for rebounnd and compression if you are plannning to equip a track car.
To ensure optimum performance and handling characteristics from the new suspension changes we selected a new set of Goodyear Eagle Exhilarate tires. The results were quite extraordinary with excellent performance, ride quality and minimal cabin noise at speed. It is especially notable that the overall performance of the car was improved despite having raised the ride height an inch and a half. We attribute that to the excellent performance qualities of the Eagle Exhilarate tires mounted on stock factory spec SRT8 wheels. For best results, be sure to obtain a high quality balance job for your new tires and have the front end alignment rechecked before putting a lot of miles on your vehicle. See the following specs to duplicate this setup. The tires are also available through Summit Racing and they look great as seen in the lead off photo of this article.

Goodyear Eagle Exhilarate

245/45ZR20
Speed Rating Y (186 mph)
Load Index 103 (1929 lbs)
Sidewall Black
Tread Life 45,000
Inflation 50 psi
Rim Width 7.5-9.0
Section Width 9.6
Tread Depth 10/32nds
Outside Dia. 28.7
Revs per Mile 729
Summit Racing PN GYT-104017568
INSTALLATION NOTES
The following tips may be useful when installing the kit on your car
* READ THE INSTRUCTIONS
* KW suspension is a German manufacturer and the instructions come in German and English.
* A clean work area and basic safety equipment such as safety goggles and gloves are recommended.
* Extra care is required when working with struts and compressed springs. Wear gloves. Be safe.
1. While individual wheels can be done with a jack and jackstands, using a lift is considerably more convenient for easy access.
2. A spring compression tool is essential. They can be rented at most local auto parts stores. The rest can be accomplished
    with normal hand tools.
3. Adjusting the rear ride height is more difficult than the front and it becomes more convenient to drop the whole assembly down
    to make the adjustment process easier.
4. We also used short bits of two by four wood blocks to gain additional compression of the springs during installation.
5. The kit requires elimination of the factory sport suspension ride adjuster, but the difference is not discernable and the car
    drives and handles beautifully even though we raised the front ride height 1-inch and the rear 1/2- inch.
6 Front adjustments are easily accomplished, but the rear requires that you drop the assembly back down to gain access with
   the spanner wrench.
7 Best performance and longevity will be derived from your new Goodyear tires if you obtain a high quality balance job and
  ensure that the front end is properly aligned to factory specs. Also pay close attention to fluctuations in tire pressure in seasonal
  weather and always run the manufacturer's recommended tire pressure.

SOURCE

Summit Racing
https://www.summitracing.com

High quality KW Suspension Kits for all late model Chrysler products are available directly through Summit Racing. Check the accompanying part numbers for direct links to the parts that fit your specific car. The variants listed refer to different spring rates that you may desire. Summit Racing carries the Goodyear tires and you can also obtain them from your local Goodyear dealer.

KW Coilover Suspension Kits for Chrysler/Dodge Cars
Coilover Springs/Struts, Natural, Purple, Yellow, Front/Rear
Click Summit Part Number for direct link

Chrysler, Dodge, 300/Magnum, V8
KW Suspensions KWA-10227016
KW Variant 1 Coilover Kits

Chrysler Magnum - 4WD 8cyl
KW Suspensions KWA-15227017 - KW Variant 2 Coilover Kits
KW Coilover Kit V2 Chrysler

Chrysler 300C - 2WD (LX) Sedan + Wagon, 8cyl
KW Suspensions KWA-15227016 - KW Variant 2 Coilover Kits
KW Coilover Kit V2

Chrysler 300's
KW Suspensions KWA-10227019 - KW Variant 1 Coilover Kits
Coilover Kits, V1
KW Suspensions KWA-15227019 - KW Variant 2 Coilover Kits
Coilover Kits, V2

Challengers/Chargers
KW Suspensions KWA-10227018 - KW Variant 1 Coilover Kits
KW Coilover Kit V1, 2011+ Dodge Challenger

Dodge, Charger, Challenger, SRT Hellcat
KW Suspensions 3A728003 - KW Variant 4 Coilover Kits
Coilover Kits, V4