CKS Coilovers with HAL Low Rebound Speed Springs for Lexus | Ryan B�s 12Kk/6kg

ModInJapan — Fri, 08 May 2026 16:30:35 GMT

We recently put together this CKS coilover setup for our friend Ryan B, using HAL Low Rebound Speed springs in a 12K front and 6K rear configuration.

This setup was built with a very specific goal: improve control, response, and chassis stability without sacrificing ride quality. Instead of simply going stiffer, we focused on spring behavior, rebound control, usable stroke, and how the suspension manages energy over real road surfaces.

Spring Specifications

Front

HAL Low Rebound Speed Springs
12 KG spring rate
203mm spring height
65mm inner diameter

Rear

HAL Low Rebound Speed Springs
6 KG spring rate
228mm spring height
65mm inner diameter

Why HAL Low Rebound Speed Springs

The biggest advantage of the HAL Low Rebound Speed spring is that it gives the suspension more control without making the car feel unnecessarily harsh. Compared to many conventional spring brands, the HAL low rebound design helps slow down how the spring releases energy after compression.

That matters because ride quality is not only about spring rate. A spring can have the same advertised rate as another brand and still feel completely different depending on how it stores and releases energy.

With the HAL Low Rebound Speed springs, the suspension feels more settled because the spring is not trying to rebound as aggressively. This allows the damper to do its job more effectively instead of constantly fighting the spring. The result is better control, better tire contact, and better performance without the sharpness or bounce that can come from a more basic high-rebound spring setup.

In real driving, this helps with:

Better composure over uneven pavement
Less bounce after compression
Improved grip through road transitions
More stable braking and corner entry
Better steering response
Reduced harshness compared to many standard coilover spring options
More usable street performance without making the car feel over-sprung

Why Low Rebound Speed Improves Control

On the street, the suspension is constantly reacting to small and medium inputs: pavement waves, dips, bridge transitions, expansion joints, and repeated surface imperfections. A conventional spring can release energy quickly, which can make the chassis feel busy or unsettled.

The HAL Low Rebound Speed spring helps reduce that aggressive return motion. By controlling the rebound behavior at the spring level, the damper has an easier time managing the suspension movement. This gives the car a more connected and planted feel without needing to over-damp the shock.

That is the key benefit: more control and performance without the ride quality penalty.

Reduced Hysteresis and Better Suspension Behavior

Hysteresis is the difference between how a spring behaves during compression and rebound. In practical terms, it affects how cleanly the spring transfers energy and how predictable the suspension feels as it loads and unloads.

A spring with poor energy behavior can make the car feel inconsistent. It may compress acceptably, but then rebound too quickly or unevenly, which can upset the chassis and reduce tire contact.

The HAL Low Rebound Speed spring helps reduce unwanted rebound behavior, making the spring and damper work together more cleanly. That improves predictability during braking, turn-in, mid-corner corrections, and repeated road inputs.

Why We Went Slightly Taller Than the Out-of-the-Box CKS Springs

For Ryan�s setup, we also went slightly taller on the springs compared to the standard out-of-the-box CKS spring configuration.

The reason was not just fitment. It was about improving how the suspension transfers and manages energy.

A slightly taller spring gives the suspension more spring material and more available working length to distribute load. That can help smooth out the way force is transferred through the spring during compression and rebound. Instead of the suspension feeling abrupt, the taller spring helps extend the energy transfer time, which can make the car feel more composed over real-world road surfaces.

In simple terms, the taller spring helps the suspension react with more control instead of feeling sharp or nervous.

This can help with:

Smoother load transfer
Better ride compliance
Less abrupt impact feel
More consistent spring behavior
Improved damper control
Better balance between comfort and performance

Why 12K Front and 6K Rear

The 12K front and 6K rear spring rate split was selected to give the car strong front-end support while keeping the rear compliant enough for traction and ride quality.

The 12K front spring helps control front-end load during braking and corner entry. This improves steering response, reduces excessive dive, and keeps the chassis more stable when the car is being driven harder.

The 6K rear spring keeps the rear of the car from becoming overly stiff or nervous. This is important on a street-driven Lexus because too much rear spring can make the car skip over rough pavement and reduce confidence mid-corner.

The result is a setup that is firm and responsive, but still usable on real roads.

CKS Coilover Package Details

This setup includes:

CKS adjustable coilover dampers
HAL Low Rebound Speed springs made in Japan
12K front spring rate
6K rear spring rate
203mm front spring height
228mm rear spring height
65mm spring inner diameter front and rear
Threaded shock bodies for ride height adjustment
Adjustable spring perches
Front upper mounts
Rear lower mounts with bushings

Overall, this CKS coilover and HAL spring setup was built for Ryan B to deliver better suspension control, improved handling response, and a more refined street ride. The key was not just choosing a spring rate. It was choosing the right spring behavior, the right spring length, and a setup that allows the damper and spring to work together properly.

For anyone researching Lexus coilovers, CKS coilovers, HAL springs, HAL Low Rebound Speed springs, 12K front 6K rear coilovers, or a more technical Lexus suspension upgrade, this setup is a good example of why spring construction and rebound behavior matter just as much as spring rate.

Photos attached for reference. Feel free to reach out to sales@modinjapan.com with questions about fitment, spring rates, ride quality, or setup recommendations. You can also learn more at www.modinjapan.com
CKS Coilovers with HAL Low Rebound Speed Springs for Lexus | Ryan B�s 12K Front and 6K Rear Setup

CKS Coilovers with HAL Low Rebound Speed Springs for Lexus | Ryan B�s 12K Front and 6K Rear Setup

CKS Coilovers with HAL Low Rebound Speed Springs for Lexus | Ryan B�s 12K Front and 6K Rear Setup

CKS Coilovers with HAL Low Rebound Speed Springs for Lexus | Ryan B�s 12K Front and 6K Rear Setup

CKS Coilovers with HAL Low Rebound Speed Springs for Lexus | Ryan B�s 12K Front and 6K Rear Setup

Is500 or rc master on a is350 f sport?

dassboot — Fri, 01 May 2026 22:54:23 GMT

Is it possible to upgrade the master from a late model IS500 or RC to a 2017 IS 350 F Sport, which has a big brake kit installed? Are the tanks on the late model IS500 vented cap?

ClubLexus - Lexus Forum Discussion - Suspension and Brakes

CKS Coilovers with HAL Low Rebound Speed Springs for Lexus | Ryan B�s 12Kk/6kg

Is500 or rc master on a is350 f sport?