Buy Now. Pay With 
Learn More
BMW M3 & M4 TUNING
F80, F82, F83 (2014–2020) and G80, G81, G82 (2021 on)
We bring the ultimate performance potential of the BMW M3 and M4 to life. The latest generations, G80, G81, and G82, are engineering marvels that redefine what it means to drive a high-performance vehicle. The M3 and M4 both feature aggressive styling, cutting-edge technology, and an exhilarating driving experience straight from the factory.
Whether you have the classic sedan (G80), the versatile touring (G81), or the sleek coupe (G82), our expert tuning services can elevate your BMW to new heights. From precision engine tuning on our Mustang 4wd dyno to installing aftermarket parts, JF Automotive is dedicated to unlocking the full potential of your M3 or M4.
Experience enhanced power, sharper handling, and a driving experience that truly reflects your passion for performance.
Which generation have you got?
Two very different engines wear these badges, and they respond very differently. Typical Stage 1 figures – yours is confirmed on our own dyno.
F80 / F82 / F83 (2014–2020) – S55 3.0 biturbo
| Model | Standard | Stage 1 | Gain | Torque |
|---|---|---|---|---|
| M3 / M4 | 431PS | 500PS | +69 | 550–600 → 680Nm |
| M3 / M4 Competition | 450PS | 500PS | +50 | 550–600 → 680Nm |
| M3 / M4 CS | 460PS | 500PS | +40 | 600 → 680Nm |
| M4 GTS | 500PS | 530PS | +30 | 600 → 700Nm |
The S55 runs Bosch MEVD17.2.G. A standard 431PS car gaining 69PS is a genuine step, and the torque figure matters more than the peak – these cars are quick everywhere once the mid-range fills in.
G80 / G81 / G82 (2021 on) – S58 3.0 biturbo
| Model | Standard | Stage 1 | Gain | Torque |
|---|---|---|---|---|
| M3 / M4 | 480PS | 640PS | +160 | 550 → 800Nm (+250) |
| M3 / M4 Competition | 510PS | 640PS | +130 | 550 → 800Nm |
| M3 CS | 550PS | 640PS | +90 | 650 → 800Nm |
The S58 is the reason the newer cars are such a big deal. A standard 480PS G80 going to 640PS and 800Nm is a far larger change than anything the S55 will give – the engine was built with more in reserve, and the factory left a great deal of it on the table.
Why the G-series is harder, and why some tuners say no
The S58 uses Bosch MG1CS024, MG1CS049 and MG1CS003 control units, which are locked from the factory. They cannot simply be read through the OBD port the way the older S55 can – the unit has to be unlocked first. That is the single reason a lot of workshops will tell you a G80 or G82 “can’t be tuned”. It can. We do it.
Tell us the registration and we will confirm exactly which unit is in your car before you commit to anything.
SELECT A STAGE...
JFA Stage 1 Tuning – 600BHP
BMW tightened ECU security from mid-2020, and traditional tuning methods stopped working overnight. Every G-Series M3 and M4 built from that point runs a locked Bosch control unit – MG1CS024, MG1CS049 or MG1CS003 – which cannot be read through the OBD port the way the older F-Series cars can. It is the reason a lot of workshops still turn these cars away.
We unlock them here, same day. Until recently the only route was shipping the control unit abroad and waiting ten to fourteen days on it. That is no longer how this works – the unlock is done on the bench at our Maidstone premises, so your ECU never leaves the building, never sits in a courier network, and you are not without your car for a fortnight.
Once it is unlocked we read it, write our calibration, and verify the result on our own Mustang 4WD dyno before the car goes back to you.
Three ways to get it done, whichever suits you:
1. SEND
Post us the ECU on its own. We will give you straightforward instructions for removing it – about a ten minute job on most cars – and we will unlock, map and return it. Useful if you are not local, or would rather keep the car at home.
2. DELIVER
Bring the car to us and we will handle the whole thing start to finish. Because the unlock is done here rather than sent away, this is a single visit rather than a fortnight without the car. A courtesy car is available if you need one.
3. COLLECT
We offer a paid collection and redelivery service on our own transporter. You do not have to arrange anything.
Not sure which control unit is in your car? Send us the registration and we will confirm it before you commit to anything.
Please note this dyno graph shows raw data measured at the wheels. Our system then calculates drivetrain losses to produce engine power figures.
We meticulously fine-tuned the ECU using our in-house Dyno and extensive daily driving with our development car. The power output can be adjusted through the BMW Drive selection modes, allowing quick adaptation to various driving conditions.
Once unlocked, we apply our latest UK fuel calibration using the Bootmod3 firmware, which includes several custom features.
Vmax Removal
Our remaps remove the top speed limiter, allowing you to exceed 155mph on de-restricted motorways or at track events.
Custom Exhaust Valve Control
Our remaps adjust the exhaust valve to enhance the exhaust note and reduce drone when cruising, especially beneficial for cars with performance exhausts or downpipes.
Optional Cold Start Removal
We offer the option to remove the Cold Start process that causes the engine/exhaust to produce a loud noise while the ECU warms up the CATs for emissions. This is particularly useful for cars without CATs.
Optional Pops & Bangs/Burbles Adjustment
You can tailor the amount of burbles produced on the overrun. Switch between OEM or custom levels using the phone app, or turn them off completely. All our remaps feature a burble setup similar to the CSL/CS models, providing a pleasant sound in Sports mode.
Pricing
JFA Stage 1 Tuning Module - 600BHP
This tuning package for the G80, G81, G82 (2021 – Present) BMW M3 & M4 utilises the Speed Buster Tuning Module, delivering 600BHP and 760Nm.
We achieve this through a fully recalibrated engine management system (Speed-Buster Module) that significantly boosts both power and torque.
Extensive testing on the road and our Mustang 4WD dyno has allowed us to enhance power and torque, not just at peak values but across the entire rev range, improving drivability and expanding the power band.
The tuning process takes about 2-3 hours. We also offer optional before and after power assessments for an additional fee.
Unlock the Full Potential of Your Vehicle with the JFA Speed-Buster Tuning Module
Transform your driving experience with the JFA Speed-Buster Tuning Module, designed to maximise your BMWs performance safely and efficiently. This module guarantees enhanced power, precision, and reliability, raising your M3’s or M4’s output to 600BHP and 760NM of torque.
Custom-Tuned Performance
Each JFA Speed-Buster Tuning Module is precisely tailored to your specific vehicle. Featuring a multi-channel loom, our modules deliver personalised performance improvements that align seamlessly with your car’s capabilities.
Easy Installation
Enjoy the simplicity of our Plug & Play system, designed to fit each type of vehicle. The installation process is quick and straightforward, taking only a few minutes. If you prefer expert installation, our UK-based support team is ready to assist you at our facility.
Trust and Reliability
- 30-Day Money-Back Guarantee: Feel secure with the option to return the product if you’re not completely satisfied.
- Made in Germany: Our modules are crafted with German engineering, known for its quality and innovative designs.
- Over 20 Years of Expertise: Benefit from two decades of specialised experience in vehicle tuning.
- 2-Year Warranty: Your investment is secure with our comprehensive warranty.
Why JFA Speed-Buster?
Choosing JFA Speed-Buster means you value quality. We maintain our product development and manufacturing in Germany, unlike many competitors who outsource to reduce costs. This commitment ensures high standards of quality and enables us to offer superior products globally.
Our modules do more than just increase power—they also boost your vehicle’s efficiency and torque by up to 30%, while protecting the engine’s integrity. Featuring genuine connectors and specially developed software, our tuning modules integrate effortlessly, resembling factory-installed components.
Please note this dyno graph shows raw data measured at the wheels. Our system then calculates drivetrain losses to produce engine power figures.
Pricing
FAQ's
Do you offer a 12 month warranty?
Coming soon…
What is motorsport use?
Motorsport-exclusive components are explicitly designed for track use. While they can be installed on any vehicle, it’s important to note that using such parts renders the vehicle unsuitable for road use and may result in MOT failure.
Will the lifespan of my engine be reduced?
No! Our remaps are designed specifically to improve the performance of your vehicle whilst remaining within the tolerances of your vehicles’ components.
Sadly, in attempt to achieve ‘big numbers’ some other companies over tune engines, placing excessive stress on the engine, transmission, cooling systems, etc, leading to reduced life span and reliability of the vehicle. We pride ourselves in producing reliable remaps which do not over stress your vehicle but still produce impressive results.
What is covered with the 30-day money back guarantee?
In any case where a customer is dissatisfied with any ecu remap software supplied, within thirty days of the supply date, the customer can request their money back. In order for any refund to be processed, the customer must present their vehicle to our workshop and allow our technicians to restore the vehicle to its original state. On successful completion JF Automotive will refund the cost of the remap to the customer.
No refund can be granted unless the vehicle is returned to the original state by JF Automotive. The 30-day money back guarantee only applies to stage 1 remaps and does not apply to other services like pops and bangs, parts or dyno sessions.
If another modification is purchased alongside a tuning file, which relies on a remap to operate, only the cost of the file is covered by this guarantee. We reserve the right to withdraw this 30 day money back guarantee.
Can the remap be reversed?
Absolutely. We offer this service free of charge if the vehicle is brought back to us. We’ll be very surprised if that’s what you want after taking one of our remap products, however in the case of lease cars some customers prefer to put the car back to standard before returning the car. You might want it back to standard if you are visiting a dealer for warranty or service work, again we will do this for free. Should you lose your tuning files due to dealer actions or parts failure we will be happy to re-install the map onto your car free of charge where possible.
What if a main dealer wipes the map with a software update?
No problem, simply bring the vehicle back in and we will take a fresh read of your ECU and write you a new map file free of charge. We offer this as part of our lifetime software support.
Do I need to notify my insurance company?
Whilst the remap is undetectable to dealer equipment, you should notify your insurance company of any modification to your vehicle. Many insurance companies do not penalise you for upgrades of this nature, particularly if you’re tuning for increased economy however a failure to disclose modifications may invalidate your policy. You may wish to enquire with your insurer if the modification will affect your policy prior to choosing one of our services.
Why we don't you offer ECU remapping for £200?!
We get asked, “Why do some tuners charge as little as £150?” There are a few factors as to why we do not offer remapping for £100-£200!
We supply custom written files for each vehicle that we remap that take in to account condition, milage and customer request of each vehicle. Our services are fully insured with a 30-day money back guarantee and lifetime support for the tuning software supplied. We constantly invest in the most up to date tuning and diagnostic equipment and software and we offer a quality service to all our customers.
Overall our custom supplied tuning software is of the highest standard that we know of, so if you want the best of the best, choose JF Automotive.
Get My Price
Try our tuning builder
Build your tune
Enter your reg and see the real power and torque figures for your exact car,
pick your options, then send it straight to us.
Open the builder →
Meet The Team
Search Tuning...
Search our ECU tuning options to increase the power and torque of your vehicle and our wide range of performance parts.