Free shipping on all orders - Details
Holley EFI

Commander 950 Pro Software Upgrade

Commander 950 Pro Software Upgrade and ECU Firmware Upgrade

Part # 534-191 Be the first to write a review
In Stock
Free Shipping
Holley Days Price
Suggested Retail
Add to Wish List
Create a new list
This is an upgrade package to migrate to the Pro Software. The Pro Software includes a host of features that add even more flexability to the Commander 950 ECU. Requires Windows 98 through XP. Not compatible with windows versions newer than XP,


  • Internal Data-Logger
  • Programmable Load Scale
  • Programmable Inputs and Outputs
  • Programmable Target O2 Voltage
  • Programmable O2 Compensation Limits
  • Wideband O2 integration
  • Deceleration Fuel Cutoff
  • Timing Trim vs. Coolant temperature

About Holley EFI

Holley is the new standard in EFI! Whether you're engine swapping your classic car or need to manage 4000 horsepower in your twin-turbocharged drag radial race car, Holley EFI has the solutions you need to get your project up and running better than ever!

Brand Holley EFI
Emission Code5
ModelCommander 950
Product TypeCommander 950 Part
Part Number534-191

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

This upgrade is included with the Wideband Oxygen Sensor upgrade P/N 534-188. Requires factory service.

    Your Review

    *Free Shipping & Handling only offered to the contiguous US on orders over $100, excludes clearance parts and oversized packages.

    Some parts are not legal for use in California or other states with similar regulations.

     X  Holleydays 2021
     X  Holleydays 2021