Ignitions and Electrical› Computers, Chips, Modules and Programmers

BMW

JB4 B58 Tuning System

$599.00

SKU: JB4-B58

In Stock
In Stock
Ships by Jul 29
Free Shipping
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The BMW JB4 is a plug-and-play tuning system designed for B58 engines. It offers significant power gains, improved turbo response, and smoother power delivery. The JB4 installs between the vehicle's sensors and the ECU, manipulating performance data without requiring permanent ECU modification.

This tuning system comes preloaded with custom software and multiple maps to accommodate various fuel types and modification levels. Features include in-dash map switching, boost limiting by gear, and support for water/methanol injection. The JB4 is also compatible with a JB4PRO adapter for wireless connection to a smartphone app, enabling data logging, map changes, and firmware updates. Optional components like downpipes and air intakes are recommended for enhanced performance.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandBMW
Part NumberJB4-B58
CategoryIgnitions and Electrical

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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