JB4 Thread for Lotus Emira AMG i4 (M139 Engine) – Tuning, Setup, Results & Support

[ManuelB]

Hi everyone,

I noticed that most JB4 discussions here are mixed between the V6 and the AMG i4 engines, which can make it difficult to find specific info for each setup. To help keep things organized and easy to access, I’m starting this dedicated thread for everything related to the BurgerTuning JB4 on the Lotus Emira AMG i4 (M139 engine).

Installation Guide (PDF):
For a step‑by‑step installation process, please refer to BurgerTuning’s official guide:
https://www.jb4tuned.com/instructions/Lotus-2.0T-JB4-Install-Guide.pdf

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Let’s use this topic to discuss:

• Installation process, tips & photos for the i4
• Map selection and custom mapping for the M139
• Dyno results and real‑world performance gains
• Troubleshooting, error codes, and solutions
• Which wires/connectors are used on the Emira i4
• Experiences with different fuel types and blends
• Integration with other mods (intake, exhaust, etc.)
• General impressions, pros & cons

Please keep posts relevant to the AMG i4!
This way, info stays easy to find for everyone looking to tune or get the most out of the 2.0 L M139 engine with the JB4.

If you’ve already installed a JB4 on your Emira i4, please share your setup, experiences, photos, and dyno charts!

Thanks to everyone contributing – let’s make this a helpful resource for all current and future Emira i4 owners.

Cheers!

 

[ManuelB]

For anyone interested in official numbers, here are the dyno results published by Burger Motorsports for the JB4 on the Lotus Emira AMG i4 (M139):

Dyno Results:

• Baseline (91 Octane): 387.5 hp / 311.5 lb-ft
• JB4 Map 1 (91 Octane, IAT Spoof): 422.9 hp / 354.9 lb-ft
• JB4 Map 2 (93 Octane): 439.2 hp / 351.6 lb-ft
• JB4 Map 3 (93 Octane): 444.3 hp / 355.4 lb-ft
• JB4 Map 4 (E30 Blend): 456.9 hp / 371.3 lb-ft

Here’s the dyno chart provided by Burger Tuning:

And for those who want to see the full testing process, check out this video from Burger Motorsports with all the dyno runs and data:
JB4 for Lotus Emira AMG i4 Dyno Results & Testing – YouTube

 

[Emira Fan]

[Baseline (91 Octane): 387.5 hp / 311.5 lb-ft]
With a parasitically loss multiplier of 12.5 % for a rear engine DCT, that suggest stock config is over 430 HP, which would be inline with C&D 0-60 figures of 3.4s

JB4 map 2 comes in around 500HP. 60 to 70 HP is a good amount of HP to pickup. Will be nice to see how everyones cars handle the additional heat from the extra 6-7 psi of boost.