What’s the difference between a Kess 3 salve and a Kess 3 master tuning tool? Tuning also known as engine remapping is the process of modifying a vehicle’s software held on the engine control unit (ECU) to improve its performance and / or fuel economy. The process is done through the use of tuning tools, which enable the vehicles software to be copied from the ECU.
The Alientech Kess is designed for this exact purpose. There two types of Kess3 tuning tools, master tools and slave tools. Here are the main difference between the Kess 3 master and the slave tool option.

Alientech Kess3 Master
The master Alientech Kess3 is designed to be used by trained professionals in a workshop / dyno setting. The master kess3 is a little more expensive. And offers a wider range of features and capabilities compared to slave tools. They are typically used to write new software onto the ECU. Hence allowing for the modification of a wide range of engine parameters such as fuel injection, ignition timing, and boost pressure.
Software can be written onto the ECU to modify fuel injection parameters, ignition timing, boost pressure. As well as many other engine parameters.
In addition to writing new software onto the ECU. The Alientech Kess 3 can also be used to clone many types of ECU’s too
The slave kess3 is designed for use by non-professional enthusiasts. They are typically cheaper and less feature-rich than master tools. Rather than being able to write new software onto the ECU. Slave tools are used to read and modify existing software. This means that the range of engine parameters that can be modified is more limited compared to a master tool.

Alientech Kess3 Slave
The Slave Kess3 is often seen as easier to use than the master option. While the physical process is reading and writing the software to teh ECU is the same on both options. The Salve tool uses new ECU files written for the tool. As such the operator does not need to write their onw tuning software.
This can make it an ideal tool option for those new to tuning. Or those that simply don’t want the hassle of writing their own tuning files.
So, what’s the difference between a Kess 3 salve and a kess 3 master tuning tool
- Price: As mentioned, the Alientech master kess3 will cost a little more than the slave version.
- Range of capabilities: The master kess3 offers a wider range of capabilities. Including the ability to write new custom and bespoke software for the vehicles ECU.
- Professional use: the master kess3 is primarily used by trained professionals in a workshop and dyno room setting. Not only writing and developing tuning software for their own use. But in most cases supplying software files to dealers and tuners operating the slave tool set up.
- Where as, the Slave kess3 is tuned by those that don’t want to write their own custom software. But have the convenience of ready to use and load software being provided.
If you are not sure which option is right for you. Mail the service and support team now for a friendly talk through the options. Or book in for one of our free no obligation training and demonstration sessions. – Contact us
You can see the full range of Alientech Kess3 tools and protocol options here in the Alientech Tuning. Shop : Alientech Kess3
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