Automobiles Technology

Civic Type R - Engineer Talk 07

"Braking performance is not only worthy of the Type R badge,
but improves traction performance as well"

Brake / VSA Engineer Kazutaka Ohmura

Brake / VSA Engineer
Kazutaka Ohmura

Specifications such as wheelbase, tread and weight distribution were reviewed along with brake distribution, and by placing bias to the rear, the new Type R is less likely to dive, maintaining a braking attitude that gives the driver confidence.

When turning after braking, it is vital to leave some of the deceleration and weight distribution to the front. This is realized by leaving a slight amount of oil pressure in the brake line even after the driver’s foot is lifted off the brake pedal, realizing stable turning.

Turning performance was also improved with a system that increases traction while turning, by applying different braking forces on each of the front tires.


Kazutaka Ohmura worked on developing the brakes, but as the new Type R’s brakes do more than slow the car down, he was deeply involved in drive stability control.

“I was involved in two aspects on brake development for the new Type R,” Ohmura explains.

“The first is brake development as a device to slow the car down. Specifications such as wheelbase, tread and weight distribution were reviewed along with brake distribution, and by placing bias to the rear, the new Type R is less likely to dive, maintaining a braking attitude that gives the driver confidence, on the road, or on the track.”

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“The new Type R’s brakes play an important role with agile handling assistance, which enhances turning performance and line-tracing abilities. If for some reason the car drifts with understeer, lightly applying the  brake to the wheel on the inside of the turn generates turning force towards the inside of the turn, effectively cancelling the understeer. If there is a difference between the front wheels in traction performance while turning close to the car’s limits, lightly applying the  brake to the wheel on the inside of the turn distributes more power to the outer wheel, and increases traction performance. This is sometimes called “braking LSD effect.” The new Type R is equipped with helical LSD, and with this brake control, enhances turning performance even further.”

How Agile Handling Assist Works

How Agile Handling Assist Works

In other words, the brakes play an important role during many situations while turning. Ohmura continues:

“I think of turning as three processes: braking, turn-in and acceleration. We aimed to increase driver confidence by improving controllability in each stage through the brakes.

“First, we realized stable braking through balance between the four wheels. With turn-in, it is important to generate load on the front through braking, but the weight is lost and the car’s nose lifts once the driver releases the brake pedal. To avoid this, a slight amount of oil pressure remains in the brake line even after the driver’s foot is quickly lifted off the brake pedal, leaving an appropriate amount of load on the front. Through this tuning, we were able to realize direct, solid braking, and brake performance that is easy to use even in city driving.

“For acceleration, the brakes provide an LSD effect, which not only realizes outstanding acceleration, but prevents the car from becoming unstable due to torque loss, resulting in stability in the turns.”

As the role of brakes expands, so will the role of Ohmura’s development team.


Civic Type R - Enginner Talk