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Independent · Maidstone, Kent · Est. 2011
Everything we do to cars.
Tuning, servicing, repairs, security and parts, under one roof on our own 4WD dyno. Start with your registration and we’ll take you straight to what fits your car.
Real Stage 1, 2 and 3 figures for your exact car - measured, not estimated.
50,000+Cars through the workshop
2,200+Reviews online
4.8 ★Average rating
4WDIn-house dyno
Tuning and remapping
Every map is written for the car in front of us and proved on our own rolling road. Nothing is loaded off a shelf.
Get your car’s figures
Enter a registration and see the actual Stage 1, 2 and 3 power and torque for your exact engine, with prices. The quickest way to find out what your car will do.
Open the builder →Stage 1, 2 and 3 explained
What each stage actually involves, what hardware it needs, and which one suits how you drive.
Read the guide →XHP gearbox tuning
ZF 8-speed and DCT gearbox software for BMW - faster shifts, higher torque limits, better manual control.
See gearbox tuning →Eco-Blue economy remapping
Written for miles per gallon rather than peak power - vans, tow cars and high-mileage diesels.
See economy tuning →Adaptive tuning module
A plug-in option where the ECU cannot be written to, or where the car needs to go back to standard easily.
See the module →Our 4WD rolling road
What a dyno actually measures, why it matters, and why we will not quote power figures we have not seen ourselves.
About the dyno →Tuning from home
Too far from Maidstone? These let you flash your own car and switch maps yourself, with our files behind them.
Powergate
Read and write your own ECU at home, hold several of our maps and swap between them whenever you like.
See Powergate →Switchable home tuning
Standard, economy and performance maps on the same car, switched by you rather than booked in each time.
See switchable tuning →JFA Touch Tune
Our own handheld tuner, pre-loaded for your car and posted out.
See Touch Tune →IXI personal flasher
A personal flashing tool for cars the handheld units do not cover.
See the IXI →Elite Flash
Gearbox and TCU flashing for cars that need the transmission doing as well as the engine.
See Elite Flash →Mobile tuning
We come to you where the car cannot come to us.
See mobile tuning →Servicing and repairs
Main-dealer schedules at independent prices, stamped and recorded, with an 85-point inspection every time.
Car servicing · from £169
Interim, full, major or your manufacturer’s own schedule. Priced from your registration, with an 85-point inspection included at every level.
See servicing and prices →Gearbox oil service
DSG, ZF and torque-converter boxes. The service most schedules quietly leave out.
See gearbox servicing →Wheel alignment
Four-wheel geometry on lowered, tuned and standard cars.
See alignment →Diagnostics and repairs
Fault finding on cars other garages have given up on, with the data to back the diagnosis.
See repairs →Air conditioning
Re-gas and leak testing for R134a and R1234yf systems.
See air con →Warranty and your car
Where you stand on servicing and tuning under a manufacturer warranty, in plain terms.
Read about warranty →Security
Keyless theft is how most modern cars go missing. This is what actually stops it.
Autowatch Ghost immobiliser · £499
An immobiliser with no key fob to clone and nothing for a relay attack to find - the car will not start without your PIN sequence. Fitted at our Maidstone workshop.
See the Ghost →Immobiliser faults
Diagnosis and repair when a factory immobiliser is stopping a car that should start.
See immobiliser work →Paint protection film
Protecting the paint on cars that get driven properly.
See PPF →Paintless dent removal
Dings and door dents pushed out without touching the paint, so the car keeps its original finish.
See dent removal →Emissions systems and faults
AdBlue, DPF and EGR systems fail expensively. We diagnose and repair them on road-going cars, and the pages below set out exactly what we will and will not do.
AdBlue and SCR
Warning lights, limp mode, injector and pump faults, and what the options are.
See AdBlue →DPF
Blocked filters, failed regens and the difference between cleaning and replacing.
See DPF →EGR
Sticking valves, coolers and the soot that causes them.
See EGR →Swirl flaps
The plastic ones that break up and get drawn into the engine.
See swirl flaps →GPF
The petrol equivalent of the DPF, and what goes wrong with it.
See GPF →Fault codes
Diagnosing persistent codes properly rather than clearing them and hoping.
See diagnostics →Trade, fleet and vans
Work that is measured in running costs rather than lap times.
Fleet tuning
Economy mapping and speed limiting across a fleet, with the paperwork to match.
See fleet tuning →Taxi and private hire
High-mileage cars where fuel is the biggest number on the sheet.
See taxi tuning →Motorhome tuning
Torque where a heavy vehicle needs it - hills, laden, and towing.
See motorhome tuning →Tuning file service
For garages and dealers: our files, written for your customer’s car.
See the dealer service →Speed limiters
Setting, raising or removing a limiter where it is legal to do so.
See limiters →Find a JFA dealer
Our approved dealers around the country.
Open the locator →Parts and cars
Supplied and fitted here, so the car goes out mapped around what is actually on it.
Performance parts
Exhausts, intakes, intercoolers, suspension and brakes, filtered to your registration.
Browse parts for your car →Exhaust systems
Milltek, Armytrix, IPE and Remus, fitted and mapped in-house.
See exhausts →Alloy wheels
Wheels and tyre packages, fitted and aligned.
See wheels →Cars for sale
Performance cars we have prepared ourselves.
See what’s available →Value my car
What yours is worth if you are thinking of moving it on.
Get a valuation →Reviews
4.8 from over 2,200 of them. Read the bad ones too.
Read reviews →Work we’ve done
Real cars, real figures, measured on our dyno.
Abarth500, 595 and 695 tuning - every stage, and the IHI turbo question
BMWPlug-in hybrids: 330e, 530e, 545e, X5 45e and i8
Porsche991 GT3 tuning and valved exhaust
TeslaModel 3 Highland on lowering springs
MercedesSprinter tuning, worked from the registration
VAGDSG and S-Tronic gearbox tuning
AudiS3, S4 and S5 - three engines, two letters
All of themEvery case study we’ve written
Common questions
Do I have to book, or can I turn up?
Book. Everything is done on our own ramps and dyno and both get busy, so a
slot means the car is worked on the day it arrives. Start with your registration on the
builder or use the contact page.
Will tuning affect my manufacturer warranty?
It can, and anyone telling you flatly that it cannot is guessing.
Our warranty page sets out where you actually stand, and
what block exemption does and does not cover on servicing.
Can you service my car as well as tune it?
Yes, and most customers do both in one visit. Servicing runs to the
manufacturer’s schedule, is stamped and recorded, and includes an 85-point inspection
- see servicing and prices.
I’m nowhere near Maidstone. Can you still tune my car?
Yes, in two ways. Powergate and
Touch Tune let you flash the car yourself at home with
our files on it, and we also run a mobile service and a
network of approved dealers.
Do you work on vans and motorhomes?
Regularly. Motorhomes,
fleets and vans are usually about torque and fuel
rather than peak power, and they are mapped that way.
Meet the team
The team behind every job
Technicians, calibrators and the front desk, all in Maidstone. No call centre and no subcontracting - the person who books you in is the person you can ask about the job.
Newsletter
Offers on parts and tuning, first
A short email now and then: new vehicle support, parts deals, open days. Nothing daily.