Cars / Vans · ECU Remapping
McLaren W1 4.0 T PHEV 1275 hp Tuning (2025–)
Factory specification and Stage 1 remap gains for the McLaren W1 4.0 T PHEV 1275 hp (2025–). A Stage 1 calibration adds 75 BHP and 110 Nm — software only, no hardware modifications required.
| Measure | Stock | Stage 1 | Stage 2 |
|---|---|---|---|
Power BHP | 1275 | 1350 +75 BHP · +6% | 1420 +145 BHP · +11% |
Torque Nm | 1340 | 1450 +110 Nm · +8% | 1500 +160 Nm · +12% |
+75 BHP
Stage 1 power gain
+110 Nm
Stage 1 torque gain
Rolling road
Dyno Graph
Power (BHP, solid) and torque (Nm, dashed) across engine speed (RPM). Peak figures match our database exactly.
Hover / touch the graph
Stock: 1275 bhp · 1340 Nm (peak)
Stage 1: 1350 bhp · 1450 Nm (peak)
Stage 2: 1420 bhp · 1500 Nm (peak)
Tuning tool compatibility
This ECU was not found in the manufacturer compatibility databases we cross-reference.
AutoTuner
Not listed in this manufacturer's data — ask us, coverage updates frequently.
Alientech KESS3
Not listed in this manufacturer's data — ask us, coverage updates frequently.
Magicmotorsport FLEX
Not listed in this manufacturer's data — ask us, coverage updates frequently.
Dimsport New Genius / New Trasdata
Not listed in this manufacturer's data — ask us, coverage updates frequently.
Existing customers upload their ECU file via the Regal Tuning File Portal. New to Regal? Request a quote first.
About this remap
McLaren W1 4.0 T PHEV 1275 hp Stage 1 — what changes
The McLaren W1 4.0 T PHEV 1275 hp (2025–) leaves the factory at 1275 BHP and 1340 Nm of torque. Manufacturers deliberately detune this engine to separate it from more expensive variants in the range — a Regal Tuning Stage 1 calibration safely recovers that headroom through the ECU alone: no hardware changes, no dyno risk, fully reversible.
Fuelling, boost pressure, ignition and torque limiters are optimised within the safe tolerances of the 4.0 T PHEV 1275 hp powertrain (hybrid petrol). The result is 1350 BHP and 1450 Nm with factory smoothness, cold-start protection and emissions behaviour retained.
Why Regal Tuning
Verified on the dyno, backed by 20+ years
Every calibration is developed and verified by Regal Tuning on an in-house 4WD dynamometer and proven across a worldwide dealer network. Your file is supplied through the Regal Tuning file portal with full technical support, and the original factory file is always kept so the vehicle can be returned to stock at any time.
Figures shown are for this exact engine variant. Gains depend on vehicle health, fuel quality and conditions — we confirm the expected output for your specific vehicle in writing before work begins.
McLaren W1 4.0 T PHEV 1275 hp remap FAQ
How much power does Stage 1 add?
Stage 1 takes the 4.0 T PHEV 1275 hp to 1350 BHP and 1450 Nm — a gain of 75 BHP and 110 Nm over stock.
Is Stage 1 safe for this engine?
Yes — software-only calibration within the safe mechanical tolerances of the engine, gearbox and drivetrain, developed and verified on our in-house 4WD dyno.
How do I get this remap?
Request a quote with your vehicle details or registration. Existing customers upload their ECU file through the Regal Tuning file portal for a fast turnaround.
20+ years of ECU calibration
Ready to unlock your McLaren W1's real performance?
Tell us your vehicle and registration — we'll confirm support and the exact expected gains for your engine before any work begins.