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JRZ RS systems benefit from 60 years of knowledge gained from supporting and developing ultra premium suspension kits for racers of all types.
The RS ONE is a single adjustable damper with 21 precise clicks of adjustment and valving capable of handling a broad range of spring rates. Through the twist of one knob, JRZ strikes a balance of adjusting both rebound and compression together. Moving between comfortable street use and aggressive track mode has never been easier. The RS ONE design minimizes complexity, while providing a significant increase in performance.
A unique compression blow off system is used to filter out large, high-velocity bumps you’d typically experience on rough streets or when attacking a berm on the race track using lower-end coilovers.
The shaft bearing has been upgraded for extended life between service intervals and to facilitate easier rebuilds. When you finally do need a refresh, JRZ has two partner service centers in the USA that can complete all necessary work.
The JRZ RS Line dampers use CNC machined internals that allow precise damping characteristics to be achieved. RS dampers are built on the same production line as the Motorsport line.
The McPherson struts from JRZ are made from high tensile steel to cope with the extreme side loads transferred from wheel to damper. JRZ applies a specialty black coating that is highly corrosion resistant, sourced from a cutting edge supplier.
If you enjoy your car predominantly on the street, these plates are for you. These are ideal for those who carve back country roads, push their luck on the occasional freeway on-ramp, or attend a few autocross or high performance driving events (HPDEs) per year. There is no metal-on-metal contact within the street plates. Instead, they use a urethane bushing as opposed to a solid metal bearing (like the race plates) to mount the strut, so they transmit far less noise, vibration, and harshness (NVH) than the spherical-bearing Race plates. If you want the performance benefits of negative camber without the metal-on-metal suspension feel, Street plates should be selected.
Pick from recommended rates or choose your own
Standard kits include 6" front & 8" rear main spring lengths with a 2.25" ID. Helper spring-ready kits include 5" front & 8" rear main spring lengths, also with a 2.25" ID. Select a helper spring-ready kit if you intend to install an optional pair of helper springs & guides on the front struts.
Ideal for daily driving and canyon carving while still delivering predictable handling you’ll enjoy on the occasional track day. Body roll and brake dive will be greatly reduced compared to stock or lowering springs. Passengers or clients likely won’t mind the increased stiffness.
Ideal for the driver who makes frequent track visits, often using performance tire compounds, and may want to drive their car to and from the track. Body roll is reduced even further than with Level 1 spring rates. Also suitable for street use, but non-enthusiast passengers may not enjoy the increased stiffness.
These are no-compromise race spring rates. Ideal for cars that see more miles on the track than on the street. This setup is for minimal body roll and maximum responsiveness, meaning on-track handling will be extraordinary at the expense of comfort on the street.
Rate Range: 400 lbs/in - 1,400 lbs/in
Length Range: 5" - 8", 2.25" ID
Select the “custom” option when configuring your kit's spring rate to display the drop-downs for selecting rates and lengths for the front and rear independently. All springs will have 2.25” inner diameters to work with the provided JRZ and Ground Control perches.
Included in every kit, these JRZ spring perches allow for precise rear ride height adjustment. They are machined from aluminum and anodized black.
To further increase service life and safe operating ranges specially designed bump stops and dust boots are included.
In order to improve the strength and performance of their rear dampers, JRZ beefed up the rear shafts from 10mm to 14mm in comparison to OEM. To account for this change JRZ includes rear pintop bushings with every set of dampers, converting the rear 14mm shafts to 10mm. This allows enthusiasts enjoying their vehicle predominantly on the street to reuse their factory 10mm rubber rear shock mounts.
For enthusiasts interested in extracting the most performance out of these high end dampers, it is vital to ensure there are no weak links amongst supplementary suspension components. We recommend track enthusiasts and racers upgrade to the optional JRZ Monoball 14mm rear shock mounts which can be directly mounted to the JRZ shafts without the extra pintop bushings. These monoball rear shock mounts are designed to significantly decrease the amount of deflection in your car's suspension which directly improves handling, driver feedback, and tire wear. Due to the solid design, it is possible to experience some added NVH.
You can upgrade your kit during checkout
Weight Jacks replace the standard rear height adjusters, to address the issue of inconsistent spring rates. Rear springs aren’t compressed straight up and down. As the control arm articulates, the spring is compressed unevenly. These weight jacks use a pivot point to keep the spring vertical throughout the range of motion. As an added benefit, ride height can be adjusted with a socket from underneath without having to pull the wheel off. These parts are BMW CCA and SCCA IT legal.
Although not required, helper springs are used to keep the main springs seated on their perches while the suspension is at full droop. When cornering hard, going over a crest in the road, or jacking up the car, the suspension has the potential to droop enough for a spring to unsettle. If that happens it can seat incorrectly the next time it’s compressed. These are highly recommended for street cars if you want to avoid a lot of the suspension related noise that’s common with aftermarket suspensions.
As a wheel company, APEX is well aware of the importance of tire to suspension clearance. For that reason we try to avoid traditional helper or tender springs as they can add a lot of stack height to the suspension. Adding an extra spring and guide to the equation ultimately lowers the position of the bottom spring perch. Doing so can result in tire interference on many BMW models, especially when wide wheel and tire configurations are used. To keep the lower perch set as high up as possible, we’ve specifically selected Hyperco’s ultra thin helper springs which are significantly thinner when fully compressed compared to most other helper springs on the market. We’ve also sourced an ultra low profile aluminum guide to hold it in place. Their stack height is very short at approximately half an inch combined.
For F-chassis M cars with EDC. This kit plugs into the vehicle’s EDC connectors and eliminates error codes resulting from the use of aftermarket dampers. Kit includes 4 cancellation units.
This kit is not mandatory, but is the quickest and easiest way to remove the error light that will be present on the dash. Alternatively, there are other solutions that can code out the error light. Choosing not to remove the error light will not impact the performance of your suspension.
|Apex Actual Price||No|
|Vehicle Chassis||BMW F8X M3/M4|
|Damper Type||Single Adjustable|