When it comes to custom performance racing and diesel engine building, Speed Performance Engines (SPR) is your local, full service expert. SPR has been in business for over 21 years. We have been building and repairing performance and racing engines for a variety of vehicles in our shop in Port Washington, Wisconsin since 2002. We are a full service automotive machine shop specializing in import, domestic, marine, light & medium duty industrial engines. We deliver quick turnaround times, and offer in-house engine dyno testing, flow bench testing and balancing.