BMW 8 Series (G15) 2019> 840i 335bhp remap figures
Thinking of remapping a BMW 8 Series 840i 335bhp? The standard car makes 335bhp and 500Nm; with a Stage 1 remap from our Leicester workshop we expect around 435bhp and 574Nm, up to +100bhp and +74Nm.
Choose your map
Stage 1 remap figures
A Stage 1 remap is a software-only change to the ECU on an otherwise standard car. It needs no extra parts, which makes it the usual starting point.
| Stock | Vanguard expected | Expected gain, up to | |
|---|---|---|---|
| Power | 335 bhp | 435 bhp | +100 bhp |
| Torque | 500 Nm | 574 Nm | +74 Nm |
All maps at a glance
| Map | Power | Torque | Expected gain, up to |
|---|---|---|---|
| Stock | 335 bhp | 500 Nm | |
| Stage 1Maximum software-only performance | 435 bhp | 574 Nm | +100 bhp +74 Nm |
| Stage 1 EcoPerformance with economy in mind | 410 bhp | 568 Nm | +75 bhp +68 Nm |
| Eco mapEconomy first | 402 bhp | 564 Nm | +67 bhp +64 Nm |
Who is the Stage 1 map for?
- Drivers who want a sharper throttle and a small, honest gain from software alone.
- Owners who would rather keep the car standard in every other way.
- Anyone who wants the fullest software-only map for this engine, accepting that the gain is modest without a turbocharger.
What this means for your 8 Series
Without a turbocharger the improvement comes from ignition, fuelling and throttle mapping rather than boost, so expect a smaller but still noticeable change in response.
Engine management is by a Bosch MG1CS201 unit. Newer ECUs often protect their software, so we read the exact unit and version on the car before confirming the figures on this page.
We remap at our Belgrave Gate workshop in Leicester, or at your home or work within 30 miles, and every job starts with a diagnostic check.
Please note: these are expected figures, not guarantees. Real results vary with the condition of the vehicle, the ECU software version, fuel quality and the hardware fitted. Some options - including Stage 2 and anything that needs extra hardware - are for off-road or competition use only. We check every vehicle first and confirm what is achievable before any work starts.
Figures reviewed 22 October 2026.
Stage 1 questions
How much power does the Stage 1 map give the BMW 8 Series 840i 335bhp?
We expect 435bhp and 574Nm against 335bhp and 500Nm as standard: up to +100bhp and +74Nm. These are expected figures, and we confirm what is achievable on your own car after a diagnostic check.
Does a Stage 1 remap need any extra parts on the BMW 8 Series 840i 335bhp?
No. Stage 1 is a software-only change to the ECU on an otherwise standard car.
Is there a gentler map than Stage 1 for this engine?
Yes, two. Stage 1 Eco is performance with economy in mind: 410bhp and 568Nm expected. The Eco map is economy first: 402bhp and 564Nm. Both still sit above the standard 335bhp and 500Nm.
Do I need to tell my insurer about a remap?
Yes. A remap is a modification, so you should declare it to your insurer.
More BMW 8 Series figures
Other petrol variants
All petrol 8 Series (G15) variants · 8 Series (G15) 2018> overview · All BMW figures