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Welcome to the Sinister Performance website!


Northeastern Indiana's Custom Performance Automotive Specialists!


We offer the following services for GM makes:

- Performance Modifications -

- Engine Swaps -

- Custom PCM and Chip Reprogramming -


We offer the following services for ALL makes:

- General Automotive Repair -


In addition to these services, we also offer information to help you improve your vehicle's performance available FREE on this website. 

Our facilities are located in Waterloo, Indiana.  If you have any questions or require our services, please email us.







In Loving Memory of:

Roy F. Rath

1930 - 2007


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