Jaguar XK 4.2 V8
ECU Remapping Cardiff
Jaguar XK 4.2 V8 in Cardiff. Standard and remapped figures for this exact engine.

- Fully dyno tested remaps
- 30 day money back guarantee
- Lifetime software warranty
- UK-wide local network
Remap stats
Jaguar XK 4.2 V8: standard vs remapped
Petrol engine. Indicative stage 1 figures, fully dyno tested.
Power
+25 bhp · +8%- Standard300 bhp
- Remapped325 bhp
Torque
+55 Nm · +13%- Standard420 Nm
- Remapped475 Nm
Tuning figures are indicative estimates, not guaranteed results. Actual results depend on the condition of the vehicle.
Prices from £130
Fully dyno tested | 30 day money back guarantee | Lifetime software warranty
Standard, the Jaguar XK 4.2 V8 makes 300 bhp and 420 Nm. With Remap Experts in Cardiff it moves to 325 bhp and 475 Nm, which adds 25 bhp (8%) and 55 Nm (13%).
Figures are indicative stage 1 estimates for a healthy petrol Jaguar XK; results vary with the condition of the vehicle.
Jaguar XK 4.2 V8 power and torque after remapping
- Fuel: Petrol
- Standard power: 300 bhp, remapped: 325 bhp (+25 bhp, +8%)
- Standard torque: 420 Nm, remapped: 475 Nm (+55 Nm, +13%)
- Service: stage 1 ECU remap, fully dyno tested
What a remap does for a petrol Jaguar XK
On a petrol car the ECU controls fuelling, spark timing and any turbo boost. A remap re-calibrates those maps within safe limits, so the car responds more eagerly and pulls harder through the rev range.
Jaguar XK 4.2 V8 against other XK engines
Ranked by power gain against the other petrol XK engines (2 in total), the 4.2 V8 is 2nd, 10 bhp below the XK petrol average of 35 bhp.
Across our whole catalogue the average petrol remap adds 27 bhp and 51 Nm, so this engine's 25 bhp and 55 Nm sits below that benchmark.
Book engine remapping for your Jaguar XK in Cardiff
Whether you live in Cardiff or nearby, the Cardiff Remap Experts site is your local route to a quote. We regularly work with drivers in Pentyrch, Rumney, Riverside, Rhiwbina and Llandaff and nearby areas of Wales.
You get a fully dyno tested remap, a 30 day money back guarantee and a lifetime software warranty with every job. Get your quote today on 0800 779 7864.
If you are closer to Gwent, Bristol and Midwales, those neighbouring Remap Experts sites can help too.

Want these figures on your Jaguar XK 4.2 V8?
Tell us about your car and we will come back with a quote by SMS or phone.
Included
What we can do for your Jaguar XK
Stage 1 ECU remap
Add power and torque and improve driveability. Software only, tailored to your engine.
ECU repair and testing
Is your engine control unit playing up? We can arrange testing and repair, and source replacement ECUs.
DPF and EGR fault repair
Persistent DPF or EGR errors diagnosed and resolved in accordance with all current road-legal standards.
Engine carbon cleaning
Fault finding and carbon cleaning for the inside of your engine, typically completed in a couple of hours.
Same model
Other XK engines
From quote to remapped in four steps
No jargon and no pressure. Here is exactly what happens.
- 01
Find your vehicle
Choose your make, model and engine to see the standard and remapped power and torque for your car.
- 02
Request a quote
Send your details and we contact you by SMS or call back with a quote. No obligation.
- 03
Book with your local site
Your local Remap Experts site arranges the remap and answers any questions about your car.
- 04
Remapped and dyno tested
Your remap is fully dyno tested, with a 30 day money back guarantee and a lifetime software warranty.
Everything you need to know
Plain-English guides to how remapping works, what it does and what to check first.
- 6 min read
What is ECU remapping?
The engine control unit, what a remap changes, and who it suits.
Read guide - 5 min read
The benefits of ECU remapping
More torque, better driveability and the potential for better economy.
Read guide - 6 min read
How ECU remapping works, step by step
From reading the original software to the dyno test.
Read guide