The C.A.T.S. RT Tuner was developed to allow ‘real-time’ ECM tuning when connected to the Xtronics (www.xtronics.com) Romulator or the Craig Moates (http://moates.net) Ostrich or AutoProm EPROM emulators. With the EPROM Emulator replacing the ECMs original EPROM, you can make calibration changes while the engine is running and the changes will take affect immediately. No longer do you need to make a change, program an EPROM and install it in the ECM to test your calibration changes.

The RT Tuner functions just like our popular Tuner program providing all the same powerful calibration editing tools, except that whenever you make a calibration change, the RT Tuner program sends the change (or changes) to the emulator. When not connected to the EPROM emulator the RT Tuner program will revert to normal ‘off-line’ (non-real-time) operation and function like the standard Tuner program.

The program is a Windows based utility developed to easily make real-time changes to GM ECM/PCM engine and transmission control parameters. The program is designed to run on 32/64 bit Windows operating systems (i.e. Windows XP and later). (For more information on installing the program on a PC running Windows 7, 8 10, or 11 please see our FAQs page.)

The RT Tuner provides the ability to change ECM/PCM calibration values without working through tens of thousands of binary bytes to determine which are computer instructions, and which are data tables, and what engine parameters these data control. You can tune a computer-controlled engine with only a basic understanding of the operation of the ECM/PCM.

With the addition of the appropriate ECM Definition File, the C.A.T.S. RT Tuner program supports a wide range of vehicles . The RT Tuner program is compatible with our current ECM Definition Files so if you're a current Tuner user there's not need to replace the ECM Definition Files you have already purchased. 


Click on this link to view the RT Tuner Quick Start Guide/RT Tuner Addendum. Follow the following link to view the full Tuner User's Manual.


Note: The Romulator I only supports EPROM’s up to 256K in size. If you select an ECM Definition File for a calibration that uses a larger EPROM, such as the $0D ECM Definition File, the program will immediately disconnect from the Romulator and revert to normal ‘off-line’ (non-real-time) operation. The Romulator II does support EPROM's up to 512K in size. The Ostrich and AutoProm support EPROMs up to 512K in size.

The Romulator, Ostrich and AutoProm emulators do not support the FLASH based PCMs supported by the $EE ECM Definition File.


Try our RT Tuner free for 30 days. To purchase a copy of the program see the 'How To Order' page for details or click the 'Add to Cart' button. As soon as we receive your order we'll send you the information to register the program.                             


If you're a currently registered user of the standard Tuner program, you can upgrade to the RT Tuner program for only $30.00. See the 'How To Order' page for details or click the 'Add to Cart' button. Note: If you're using a version of the Tuner program earlier than 1.98 you can still upgrade for $30.00 but you will have to download the full install for the RT Tuner.                             


Additional ECM Definition files are available for $19.95 USD. See the 'ECMs Supported' Page for a list of currently available ECM Definition Files.