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ThunderMax ECM Performance Auto Tuner For Harley Softail 2018-2020

Item: P998492
Customer rating is 4.5 out of 5 stars.
122 Read 122 Reviews Read6 Q&As(Questions and Answers) Write a Review

The ThunderMax ECM With AutoTune Closed Loop System is the high-tech way to manage every aspect of your fuel curve for the best throttle response avai… Read More

Current price is $1,088.95
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This product DOES NOT FIT your 2026 KTM 390 Duke

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Product Details

ThunderMax ECM Performance Auto Tuner For Harley

The ThunderMax ECM With AutoTune Closed Loop System is the high-tech way to manage every aspect of your fuel curve for the best throttle response available in an aftermarket fuel system manager. It mounts conveniently in place of your factory ECM and plugs into your existing harness, and uses a closed-loop control system to continuously self-adjust and properly tune the motorcycle's air/fuel ratio for all riding conditions. If you start at sea-level and ride up to a mountain pass, the ThunderMax will automatically adjust your tune to keep your engine running cool and happy!

There are plenty of piggyback tuners on the market that simply modify your ECM (electronic control module) they are capable of making basic adjustments suitable for mildly upgraded bikes, but none of them can make real time adjustments while you ride. For that type of performance you need a closed loop tuner and the ThunderMax ECM replacement is one of the best! Consider it a brain transplant for your bike! The ThunderMax system utilizes wide-band O2 sensors, along with your bikes factory sensors to monitor and adjust your air-fuel ratio in real time!

Every degree and a half of throttle rotation or 256 RPM, there is a fueling point that is automatically adjusted. That means more control and a smoother running engine. With the built in barometric sensor you never have to think about ambient air changes. WideBand O2 sensors constantly read the Air Fuel Ratio and give live, real time feedback to the ECM. That means, no “accepting” the changes made to the map, once you key off the changes are written. The ThunderMax ECM is fully adjustable with their free tuning software or can be used just by loading a base map. 

Features:

  • Mounts in place of factory ECM
  • Real time auto-tune adjustments
  • Start with a base map then let auto tune dial in your ride
  • Compatible with high-performance camshafts, turbo, nitro and superchargers
  • Monitor, record and analyze diagnostic codes and stats
  • Free firmware, tech support and updates

Note: System requires 18mm O2 sensor ports to accommodate the wideband sensors, stock pipes will need to have the 12mm bungs removed and 18mm bungs welded in place.

Product Style RevZilla Item # Store Sku MFR. Product # Availability
Product Style ThunderMax ECM Performance Auto Tuner For Harley Softail 2018-2020 RevZilla Item #10223949 Store Sku330285 MFR. Product #309-589 AvailabilityOnly 2 Left: Ships within 24 hours
Please review this product's fitment notes & exceptions prior to purchase: Add to Cart

This product DOES NOT FIT your 2026 KTM 390 Duke

Fitment Notes & Exceptions
  • This product is not legal for street use on an emissions-controlled vehicle. It may be used on dedicated competition or pre-pollution-controlled vehicles only.
  • Will require the use of an exhaust system with 18mm sensor bungs or head pipes must be modified to accept 18mm sensors.
This Product Fits
Harley Davidson
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Softail Fat Bob 114 FXFBS 2018, 2019, 2020
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Softail Fat Boy 114 FLFBS 2018, 2019, 2020
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Softail FXDR 114 FXDRS 2019, 2020
Softail Heritage Classic 114 FLHCS 2018, 2019, 2020
Softail Heritage Classic FLHC 2018, 2019, 2020
Softail Low Rider FXLR 2018, 2019, 2020
Softail Slim FLSL 2018, 2019, 2020
Softail Sport Glide FLSB 2018, 2019, 2020
Softail Standard FXST 2020
Softail Street Bob FXBB 2018, 2019, 2020
This item is also available for 33 different vehicles. View All Models
Product Description
Part Numbers
Fitment
122 Customer Reviews for All Models
Customer rating is 4.5 out of 5 stars. 122 total customer reviews 4.5/5
6 Questions & 26 Answers for All Models

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