4.2 V8 supercharged - 400ch Tuning
Jaguar XJ — Detailed power and torque gains by stage.
Gains by stage(4)
Power
400 hp
Torque
541 Nm
essence
Power
400→470ch
+70 ch
+18%
Torque
541→630Nm
+89 Nm
+16%
OriginalTuned
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Everything about 4.2 V8 supercharged - 400ch tuning
Tuning the 4.2 V8 supercharged - 400ch found in the Jaguar XJ is one of the most popular performance upgrades. This engine offers excellent potential for power and torque gains.
On ChiptuneMAP, find verified gain data for each stage, compare tuner prices and find the ideal professional for your project.
Gains summary by stage
On the Jaguar XJ 4.2 V8 supercharged - 400ch, tuning delivers up to +120 hp and +149 Nm depending on the stage. Stock vs tuned figures:
| Stage | Power | Torque | Indicative price |
|---|---|---|---|
| Stage 1 | 400 → 470 hp | 541 → 630 Nm | — |
| Stage 2 | 400 → 520 hp | 541 → 690 Nm | — |
| E85 Flexfuel | 400 → 400 hp | 541 → 541 Nm | — |
| E85+ | 400 → 470 hp | 541 → 630 Nm | — |
Frequently asked questions
What gains can I expect from tuning the 4.2 V8 supercharged - 400ch?
Tuning the 4.2 V8 supercharged - 400ch (Jaguar XJ) delivers significant power and torque gains depending on the chosen stage. Stage 1, with no hardware modifications, offers the best gain-to-reliability ratio.
Is tuning reliable on the 4.2 V8 supercharged - 400ch?
Yes, the 4.2 V8 supercharged - 400ch is known for its reliability when tuned, especially at Stage 1. It's essential to use a certified tuner with maps tailored to your engine.
How much does Jaguar XJ tuning cost?
Prices vary by stage and tuner. Check our directory to compare rates from professionals near you.
Should I get a tuning box or an ECU remap?
ECU remapping (modifying the engine control unit map) delivers better results and integration than a plug-in tuning box. It's customized for each engine.
How do I find a tuner for my Jaguar XJ?
Use the ChiptuneMAP directory to find a certified tuner near you. Compare reviews, prices and specialties.