Maruha BC Damper Kit: Genuine NB Upper Mount Version

We hope more users will feel free to upgrade their car's performance.

Maruha's BC Damper Kit line, which was designed as a MIATA suspension, features a wide variety of functions.
Our genuine NB upper mount version is more reasonable than the pillow ball upper mount version, and furthermore, it suits your street drive best.
We guarantee that everyone who has been looking for ideal damper will be fully satisfied with the product.

Many pillow ball upper mounts on the market have splendid durability by using large pillow balls.
However, these balls are two sides of the same coin.
Some people point to them as unneeded specs under street drive conditions.

Maruha has developed a more street-oriented damper for street users' needs. Our motto is: "Simplify the functions and create a more comfortable drive."
Through trials and errors we released the genuine NB upper mount version, which has enough strokes.
You can install it in all MIATAs - NA and NB series too.

1. The kit contents and functions

Except for the genuine NB upper mount body, Maruha designs all the parts of this product.
The body case is a single tube shell case that can radiate heat immediately.
It is made of off-black plated drawn steel wire to achieve a low-friction and anti-abrasion feature of a piston.
This piston has 46.0mm diameter that is the largest in the line of the MIATA series and its durability and capacity are on the top.

The 15-speed adjustment click shock absorber adjusts damping force at the top of the click shaft and you are able to use it for severe conditions such as cross-ridges and circuit drives. When we show its performance as the spring rates, the shock absorber can withstand until Front 12.0kg/mm and Rear 10.0kg/mm in hard drives, while in street use, F 4.0kg/mm and R 4.0kg/mm (basic rates are F 8.0kg/mm and R 6.0kg/mm).

The adjust bracket, which is an overall height adjustment tool placed on the bottom of the damper tube, can finely adjust the car height as you like, even though there is no spring allowance without any helper springs.

2. Long life & high performance: the genuine NB upper mount

The best quality suspension for street drive, intended for enjoyable drive and dynamic steering control, is coming up!

In order to enhance the product's life cycle, we use some genuine parts including the upper mount body and the bushes fixed on the top and bottom of the upper mount.

The genuine NB upper mount features a billet aluminum upper mount sheet on the bottom of the upper mount. The sheet prevents the spring from setting out of place.
These genuine parts allow us to offer you a high-quality and reasonable damper that has complete functions, high performance and superb durability.

Maruha BC Damper Kit can match the needs of many street users who drive the cars in the lowest height on the street.

3. More durable rod

The rod, including the adjusting shaft and the damping shaft, has the 15-speed adjustment click shock absorber on the top of it.
We make the rod diameter larger to get enough strength.

4. Spring rates

The spring rates are F 8.0kg/mm and R 6.0kg/mm.
They allow you to turn in sharp corners with less anxiety, though the spring is basically designed for street use.
As the result of improving the gas pressure and the shim stack, the rates can work the spring to display its real performance in comfortable but sporty street driving.

What you may need for the spring in street use are not only to free your car from a rough handling, but to obtain a smoother steering and enough strokes.
In order to respond to your needs, we keep adequate roll for drivers to handle the cars without uncomfortability.

5. Car height adjustment devices

The spring lower seat, which is made of aluminum, moves about 2.0mm up and down at one revolution.

Once you have got a Maruha BC Damper Kit, our spring lower seat offers you fine opportunities to enrich your car.

The spring lower seat has not only the role to avoid the spring allowance but also brings you an advantage to arrange the spring preload as freely as you wish by using the adjusting bracket together.
Whenever the lower seat and the adjusting bracket, so called an overall height adjustment system, are placed on the bottom of the damper tube, you can adjust the spring preload without changing your car height.

Moreover, higher spring rates are available through tightening up the lower seat.
You never need to change the spring. But then, you will find your car height higher.
You don't have to worry.
All you do is lower it with the adjusting bracket.

If you make full use of the spring lower seat, you will get a more exciting experience of suspension tuning.

6. Accessories

A. Wrench set for car height adjustment

PENETRATE LUBE, which is an anti-corrosion penetrating fluid, is also an accessory of Maruha Racing Thread Control Kit.

If you are interested in a pillow ball upper mount, visit “Maruha BC Damper Kit: Pillow Ball Upper Mount Version” page.


Maruha Motors Co., Ltd.
Ushizuma 2095-6, Aoi-Ward
421- 2106 Shizuoka city, Shizuoka prefecture
TEL: 0081-54-294-0076
FAX: 0081-54-294-1312