Big Brake Kits And Electronic Handbrakes: What Fits And What Does Not
This is the question we get asked most about modern cars, and the one the industry has been worst at answering. The car has an electronic handbrake, a button instead of a lever, and the owner wants a big brake kit. Can it be done, and what happens to the parking brake?
The honest answer has three parts, and only one of them is complicated. The front axle is unaffected and always has been. The rear axle is where the problem lives. And as of late last year there is finally a proper solution for the rear, though it is new and it does not yet cover many cars.
- The parking brake motor lives in the REAR caliper, so front kits do not touch it
- Replace a rear caliper on an electronic handbrake car and the motor has to go somewhere
- Tarox launched a caliper built to take the original motor, the E34, in November 2025
- Every rear kit we currently list is written for a cable handbrake, so ask before you order
Why the electronic handbrake changes things
On an older car the handbrake is a cable. It runs from the lever to a mechanism inside the rear brake, and that mechanism is part of the caliper or a small drum inside the disc. Fit an aftermarket rear caliper designed for that car and the kit is built around the same arrangement, which is why our rear kits say what they say.
On a car with an electronic parking brake, the button on the console operates a small electric motor bolted to the back of each rear caliper. That motor drives the piston out to clamp the pads when you park. The parking brake is not a separate mechanism any more, it is a function of the rear caliper itself.
So the moment you take a rear caliper off an electronic handbrake car, you have removed the parking brake. Not weakened it, removed it. The replacement caliper has to accept that motor, or the car has no working handbrake and a dashboard full of warnings, and it is not going to pass an MOT in that state.
Cable handbrake
Lever, cable, and a mechanism inside the rear brake. An aftermarket rear kit for that car is designed around it, and the parking brake carries on working as before. This is most cars up to roughly the mid 2010s, and everything our current rear kits are written for.
Electronic parking brake
Button, wiring, and a motor bolted to each rear caliper driving the piston. The caliper IS the parking brake. Change it for one that cannot take the motor and you have no handbrake, so the rear axle needs a caliper designed for the job.
The front axle, the easy answer
Here is the part that gets lost in the noise. The electronic parking brake is a rear axle system. Nothing about it involves the front calipers, so a front big brake kit on an electronic handbrake car raises none of these questions at all. You fit it exactly as you would on any other car.
That matters because the front axle is where the braking happens. Weight transfers forward under braking, and the fronts do the overwhelming majority of the work, which is why nearly every kit we sell is a front kit and why our advice on almost any car is to start there. If you drive something modern with a button handbrake and you want more brake, the front kit is very likely the whole answer, and it is available today for a long list of cars.
The rear axle, the real question
If you genuinely need the rear as well, and most road cars do not, there are only two honest routes.
The first is a caliper designed to take the original parking brake motor, so the electronics carry on working exactly as the manufacturer intended. Until recently that barely existed in the aftermarket, which is why so many people were told a flat no.
The second is anything that leaves the original rear caliper in place, because if the caliper stays, the motor bolted to it stays too. That is exactly what a big disc kit does: it fits an oversized disc to the car’s original caliper on a relocation bracket, so the parking brake mechanism is never disturbed. On paper that makes a big disc kit the natural route on an electronic handbrake car, and it is usually the cheaper one as well.
We would still check it against your specific vehicle before taking an order. Clearance and bracket design vary car by car, and EPB arrangements changed part way through the life of several models. The principle is sound; the fitment is still a conversation.
What Tarox have done about it
Tarox showed a caliper built specifically for this problem at SEMA in Las Vegas in November 2025. The E34 is a four piston billet alloy caliper that, in their words, is ready for motors integration and integrates with the OEM handbrake motor. In plain English: the factory parking brake motor transfers across onto the performance caliper, and the button on the console keeps working.
The clearest published example is their Land Rover Defender kit. The rear, part number KMLR1377, pairs 370mm single piece rotors machined from solid billets on floating alloy bells with the E34 four piston calipers ready for motors integration, fitted with Enduro pads. The matching front, KMLR1380, uses the same 370mm rotors with the F36 six staggered piston caliper. Tarox list the Alfa Romeo Giulia and the Jaguar F-Type as the other launch applications.
It is worth understanding what this is and is not. It is a genuine engineering answer to a problem the aftermarket had mostly been ignoring, and it will spread to more vehicles over time. It is not, today, a solution for the average electronic handbrake car, because three applications is three applications. Anyone telling you the rear of your modern hatchback is a solved problem is ahead of the evidence.
What our listings actually say
Read the kit description before you read the price. Our rear Tarox kits carry a specific line, and it is the line that matters here: compatible with standard handbrake. Standard means the cable arrangement described above. Those kits are written for cars like the Golf Mk4, the 200SX and the Skyline, none of which have an electronic parking brake, and the wording is accurate for them.
What that line does not do is tell you about a car it was never written for. If you are looking at a rear conversion kit and your car has a button instead of a lever, treat the listing as unanswered and ask us.
The big disc listings are more explicit, and worth reading closely if you are on an electronic handbrake car. They describe fitting an oversized rear disc to the car’s original caliper, with a spacer bracket moving that caliper out to suit the bigger disc, so the standard handbrake carries on working and the ABS and ESP are untouched. That is the arrangement that leaves an electronic parking brake motor undisturbed, because the caliper it is bolted to never comes off. The car selector will show you what exists for your vehicle, and if you are choosing disc faces at the same time, the disc guide covers that decision.
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Nissan 200SX Brake Kits, Hi Spec Road Car Rear Big Brake kits, Tarox 330mm 6 pot sport conversion kits
£2,280.00 Incl. VATPayPal CreditFinance availableSelect options -
TAROX Rear Big Disc Upgrades, Volkswagen Big Disc Kits
£1,074.00 Incl. VATPayPal CreditFinance availableSelect options
What we need from you to check
Four things, and it takes about five minutes on the phone. The exact vehicle, including the year and the engine, because the parking brake arrangement changed part way through the life of several models. Whether the handbrake is a lever or a button, which you can answer from the driver’s seat. Your wheel size and the make and model of the wheel if it is aftermarket, because clearance is Cameron’s first question on any kit. And what the car is actually for, road, track days or something more serious.
With those four we can tell you what is available for the front, whether there is any rear option worth discussing, and whether the answer is simply that the fronts are enough. Often it is.
Common questions
Can I fit a big brake kit to a car with an electronic handbrake?
On the front, yes, in exactly the same way as any other car. The electronic parking brake is a rear axle system and the front calipers have nothing to do with it. The rear is the part that needs checking, because the parking brake motor is bolted to the rear caliper.
What happens if I fit a rear caliper that cannot take the motor?
You have no parking brake. The button will not do anything useful, the car will report a fault, and it will not pass an MOT like that. It is not a case of the handbrake being weaker, the mechanism has physically gone. That is why we check before quoting on any rear kit for a modern car.
Do you sell the Tarox E34 kits?
Not on the website at the moment. Tarox launched the E34 caliper in November 2025 with kits for the Defender, the Alfa Romeo Giulia and the Jaguar F-Type. If you have one of those, ring us and we will speak to Tarox about availability and price for your car instead of guessing at it here.
Would a big disc kit avoid the problem?
Usually yes, and it is the route we would look at first. A big disc kit fits a larger disc to your car's original caliper on a relocation bracket, so the parking brake motor stays exactly where the factory put it. It is also cheaper than a full conversion. What we will not do is promise it for your car without checking, because bracket design and clearance vary by vehicle. Tell us what you drive and we will confirm it before you order.
My car has a lever. Does any of this apply?
No. If you have a conventional handbrake lever, the rear kits on the site are written for exactly that and the compatible with standard handbrake line means what it says. This whole page is about cars with a button on the console.
Is a rear upgrade even worth it?
On most road cars, no. The front axle does the great majority of the braking, and putting money into the rear before the front gets the balance the wrong way round. Rear upgrades earn their place on heavier cars, on cars used hard on circuit, and where you are chasing balance more than outright stopping power. Ask us before you spend, because the honest answer is often that you do not need it.
What we would do
Nine times out of ten, on a modern car with a button handbrake: fit a front big brake kit, run a decent pad, and leave the rear axle exactly as the factory built it. You get the braking improvement where the braking actually happens, the parking brake keeps working, and the MOT is somebody else’s problem.
If you have a Defender, a Giulia or an F-Type and you want the rear doing properly as well, the Tarox E34 route now exists and it is worth a conversation. Ring us on 0115 9893488 with the car, the year and your wheel size and we will tell you what is genuinely available, including when the answer is that the fronts are enough. Garreth would rather sell you one kit that works than two that cause an argument.