Bosch Motorsport M5 ABS Integration Kit for Toyota 86 / Subaru BRZ — in final development
A Bosch Motorsport M5 ABS integration kit for the Toyota 86 and Subaru BRZ is in 909’s development program now.
The Bosch Motorsport M5 ABS is a professional-level motorsport unit used in racing worldwide. It provides ultra-fast processing, highly accurate wheel slip control, and configurable ABS strategies for track use. Eleven selectable calibrations on a 12-position map switch allow the ABS behaviour to be tuned for tyres, surface conditions, and driving style.
These cars fill grids and track days in numbers, and they get driven properly — which is exactly the condition in which a road braking calibration starts showing its limits.
The problem with factory ABS in competition — what track drivers call “ice mode”
ABS works by holding each tyre near a target slip ratio — the difference between wheel speed and vehicle speed, where 0% is a freely rolling tyre and 100% is a locked one. Peak braking force sits somewhere between the two, and exactly where depends on the tyre and the surface. The cycling you feel through the pedal is the system chasing its target, and while it’s in slip control, pressing harder adds nothing — extra pedal force won’t be sent to a tyre the system already considers at its limit.
Road-car calibrations have to be built conservatively: one calibration must stay safe on every surface a road car can meet, down to the very worst. Under genuine circuit braking — real speed, semis or slicks, kerbs and bumps working the tyre — that conservative logic can settle on a slip target far below the grip actually available. The result is what drivers call ice mode: the system refuses to build brake pressure no matter how hard you stand on the pedal, and the only way out is to come almost completely off the brake, let the wheels match the car’s speed, and reapply. If you braked at the limit for the corner, that margin doesn’t exist.
It isn’t a fault, and pads, fluid or bigger discs won’t touch it — it’s a road calibration operating outside the envelope it was designed for.
Motorsport ABS approaches the problem from the other direction: the driver selects the calibration for the tyre and conditions actually in use, and the system controls to a slip target appropriate for genuine circuit grip. Eleven selectable calibrations on the 12-position map switch cover the range from wet circuit to slicks — chosen before the braking zone, not discovered during it.
If you race one, you have already had this argument
Ice mode is a familiar topic in 86 Cup and one-make 86 racing — and it is argued about as much as it is described. Plenty of the discussion lands on it being driver technique, or pad choice, or brake temperature, or someone simply not braking hard enough. Owners who have felt the pedal go long and unresponsive mid-session tend to be less easily talked out of it.
Both things can be true. Technique and temperature genuinely matter, and none of them change the underlying mechanism: a single road calibration, written to stay safe on the worst surface the car might ever meet, deciding on your behalf that the tyre is already at its limit. On a well-driven car on good rubber, that decision can be made a long way short of the grip available.
Most of the conversation is around Gen 1, because that is where the racing has been. Nothing about Gen 2 changes the principle — the same road-calibration logic is doing the same job — so as those cars get raced harder, the same argument will follow them.
Brake balance: what the factory system quietly manages for you
On a platform like this the ABS/ESP doesn’t just prevent lock-ups — it actively manages front-to-rear brake distribution. Under light braking the system can run more rear brake than the hydraulics alone would give, keeping the car flat; under hard braking it bleeds rear pressure down as weight transfers forward. The distribution your car actually runs is electronic, not mechanical.
That has two consequences for a competition build. Unplugging the ABS doesn’t return the car to some honest pre-electronic state — it removes the brakeforce distribution the base hardware was designed around, and can leave the car with a hard pedal and a rear balance never intended to stand on its own. And altering mechanical bias underneath a stock system means fighting a computer that’s redistributing pressure on top of your changes.
A motorsport ABS conversion makes brake balance deliberate again: the overall front-to-rear balance is set properly in hardware — which is why 909 kits include bias valve mounting provisions — and the M5 then controls slip at each wheel from that correct baseline, rather than papering over an incorrect one.
In final development
The 86 / BRZ integration kit is in 909’s development program now. Register your interest and be first in line for fitment details, pricing and the first production kits — and tell us about your build; development cars occasionally get early access.
What a 909 integration kit means
Across our released platforms, a 909 kit is the vehicle-specific engineering around the Bosch Motorsport M5: wheel speed sensing designed for the hubs and axles the car actually runs, hydraulic unit mounting in a location we have tested, cabin hardware bracketed rather than improvised, and calibration support behind it. That is the standard the 86 / BRZ kit is being developed to.
On every 909 kit, brake lines from the master cylinder to the hydraulic unit are made to suit the vehicle at install — 909 specifications call for Goodridge or Speedflow hardware.
Technical Specifications – Bosch Motorsport M5 ABS
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Control Strategy: High-speed multi-channel wheel slip control
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Maps: Eleven selectable calibrations on a 12-position map switch
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Inputs: 4x wheel speed sensors
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Outputs: Hydraulic modulation via Bosch Motorsport valve block
Bosch Motorsport M5 vs Factory ABS
|
Factory 86 / BRZ ABS |
Bosch Motorsport M5 ABS Kit |
| Technology |
Road-car ABS module with stability functions |
Modern, high-speed multi-channel motorsport ABS |
| Processing Speed |
Limited, slower ECU response |
Ultra-fast ECU with real-time wheel slip control |
| ABS Maps |
Fixed road calibration with selectable driving modes |
Eleven selectable calibrations for different tyres and conditions |
| Brake balance |
Electronically distributed by the factory module |
Set deliberately in hardware, with slip controlled at each wheel from that baseline |
| Driver Control |
Driving mode selection only |
Driver-selectable map switch, adjustable between sessions |
| Performance |
Adequate for road use; limited under hard braking/track |
Motorsport-level braking performance for the track |
| Adjustability |
None |
Adjustable for tyres, surface conditions, and driver preference |
FAQs
Q: When can I buy one?
A: The kit is in final development and pricing has not been released. Register your interest and we will come back to you with fitment details and timing as soon as they are confirmed.
Q: Which generation will it suit?
A: Fitment detail is being confirmed through development. Gen 1 is where most of the racing has been and where the demand sits today; Gen 2 runs the same road-calibration logic and will raise the same questions as those cars get campaigned. Register your interest and tell us which car you have — it genuinely informs where the work goes first.
Q: Why not just unplug the ABS instead?
A: On this platform that also deletes the electronic brake distribution the car was designed around, leaving a rear balance that was never meant to stand on its own. A motorsport system with properly set mechanical balance is the engineered path, not the workaround.
Q: I’m building a car now — can it be a development car?
A: Possibly. Get in touch and tell us about the build and how the car gets used. Development cars occasionally get early access.
Q: Will installation need brake lines made?
A: Yes. On every 909 kit the lines from the master cylinder to the hydraulic unit are made to suit at install. Professional installation is recommended, and we can install and commission in our Newcastle workshop.
Q: Can you ship overseas?
A: Yes. 909 vehicle-specific kits ship worldwide. Contact us for freight to your country.
Q: Is the system validated for road use?
A: No, Bosch Motorsport ABS is for track usage only.
Q: Will this kit suit a LHD car?
A: Development is on a RHD car. For the right pilot customer we would be willing to work together on LHD testing — please get in touch via the contact page.
