Typical before and after power and torque for every BMW 4 Series engine we tune. Your own car is custom mapped on our in-house 4WD dyno, and every map is fully reversible.
Locked ECU? No problem. BMW and Alpina cars built from June 2020 have an encrypted ECU. We unlock it on our own bench the same day — £100 added to a tuning booking — and it adds no time to your appointment. On its own, if we’re not tuning the car, it’s £249. Check your reg → · More on unlocking →Built from June 2026? Those cars use a new ECU lock that can’t yet be opened, so we can’t tune them for now. Email sales@dcremappinguk.com with your reg and we’ll let you know as soon as that changes.
Locked ECU? No problem. BMW and Alpina cars built from June 2020 have an encrypted ECU. We unlock it on our own bench the same day — £100 added to a tuning booking — and it adds no time to your appointment. On its own, if we’re not tuning the car, it’s £249. Check your reg → · More on unlocking →
Locked ECU? No problem. BMW and Alpina cars built from June 2020 have an encrypted ECU. We unlock it on our own bench the same day — £100 added to a tuning booking — and it adds no time to your appointment. On its own, if we’re not tuning the car, it’s £249. Check your reg → · More on unlocking →
Stage 2 Petrol supporting mods: decat or sports cat + uprated intercooler.
Every price on this page is a full custom dyno tune
Not a generic file bought in and flashed over the port. Your BMW 4-Series is strapped to our in-house 4WD dyno and the map is written for your car, on the day, from its own data.
Health check firstWe look the car over and read the fault memory before we touch anything. If something is wrong, you get told. We don't map over a problem.
Live data loggingBoost, timing, fuelling and temperatures all watched in real time under load: knock on the petrols, rail pressure and exhaust temps on the diesels.
Custom calibration on the dynoThe map is built and adjusted run by run against what your engine is actually doing, not what a file supplier assumed.
Before and after printoutYou leave with the graph: your standard figures and your tuned figures, measured on the same rollers, the same day.
Spread the cost. From £74.83/mo over 6 months at 0% APR with Bumper, interest free. Or choose Pay in full when you book and pay with Klarna. How finance works › Book engine and gearbox tuning together and save £125.
BMW 4-Series remapping questions
What gains can I expect from Stage 1 on a BMW 4-Series?
It depends which engine you have. Across the 38 BMW 4-Series engines we tune, the 440i sees the biggest Stage 1 gain: 326bhp to 420bhp and 450Nm to 600Nm, up 94bhp. Every figure on this page is for that exact engine.
How much does it cost to remap a BMW 4-Series?
Stage 1 custom dyno tuning on a BMW 4-Series starts at £449 inc VAT, and gearbox tuning is £325 or £385 depending on the model. Book both together and you save £125. You can spread it over 6 months at 0% with Bumper, or choose Pay in full when you book and pay with Klarna.
Does my BMW 4-Series need its ECU unlocking?
If it was built from around June 2020 onwards, yes. Those ECUs are locked from the factory and have to be unlocked before anything can be written. We do it in-house. Check your registration and we will tell you straight away whether yours is affected. Check if your ECU is locked ›
What does Stage 2 need on a BMW 4-Series?
It depends on fuel. Diesels need a DPF delete (off-road use only) and an uprated intercooler; petrols need a decat or sports cat downpipe plus an uprated intercooler. Stage 2 cannot be mapped safely on a standard car, so if yours has no supporting hardware we will fit Stage 1 instead.
Will remapping my BMW 4-Series affect my warranty or insurance?
You will need to tell your insurer, as with any modification, and it can affect a remaining manufacturer warranty. Every map is reversible, so the BMW 4-Series can be put back to its factory software at any point.
How long does it take, and is it reversible?
Allow roughly two hours for Stage 1. A locked ECU is unlocked in-house on the same visit without a longer appointment. Everything is reversible: the BMW 4-Series can go back to its factory software on request.
Ways to paywhen you pay in full0% finance over 6 monthsCard & Apple Pay£50 deposit secures your slotHow finance works ›
Whichever you pick, the total carries through to checkout, so pay in full by card, Apple Pay or Klarna, or secure the slot with a £50 deposit. Figures are typical for a healthy, standard vehicle; your before and after dyno printout shows exactly what your car makes. Your car’s actual output depends on its condition, fuel quality and any supporting modifications. Prices shown are for Stage 1 custom dyno tuning inc VAT; locked ECUs (most BMW and Audi registered from mid-2020) carry an additional unlocking charge, confirmed when you book.
We use essential cookies to make this site work. With your consent we also use cookies to measure traffic and improve our marketing. See our Privacy Policy.
·
★ 4.9 · 264+ Google reviews
·
In-house 4WD dyno · before & after printout
·
BMW ECU unlocking · in-house, same day
·
0% finance with Bumper · spread it over 6 months
·
10,000+ vehicles tuned · 14+ years
·
BMW & VAG specialists · Warrington
·
Pay with 