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Ignitions and Electrical› Computers, Chips, Modules and Programmers

ThunderMax

ECM Replacement with AutoTune

$1,100.00 $750.00 Save $350.00

SKU: 309-591

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

Moderate — 2–4 hours

Description

The ThunderMax 309-591 is an ECM replacement for EFI-equipped Harley-Davidson motorcycles. It features proprietary AutoTune technology for real-time air/fuel ratio adjustment and a built-in barometric sensor for automatic altitude compensation. The system includes knock correction for timing adjustments and supports factory functions.

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

BrandThunderMax
Part Number309-591
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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