Downloading Hondata s300 1.5.4.0 from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this software available. The Hondata s300 installer is commonly called SManager.exe. This program was originally produced by Hondata, Inc.
Please note that it is recommended to check the downloaded files with any free antivirus as we cannot guarantee that they are safe. The following version: 1.5 is the most frequently downloaded one by the program users. Hondata s300 is included in Security Tools.
From the developer:
Hondata s300 is a plug in module to the factory Honda Engine Computer (ECU) which vastly expands the capabilities of the factory ECU. Forced induction, datalogging, real time updating of parameters, engine protection are but a few of the s300 features.
You may want to check out more software, such as Hondata FTDI USB Driver Fix, which might be similar to Hondata s300.