Subaru says the performance boost is significant: up to 30 horsepower and 20 pound-feet on a stock 2007 STI and up to 10 hp and 17 lb-ft on a stock WRX, and up to 30 horsepower and 30 pound-feet on a stock Legacy GT.The SPT Performance Exhaust replaces the stock intermediate pipe and muffler with a larger, 3-inch stainless-steel system for better sound and performance. The SPT High Flow Air Intakes are made of cast aluminum and come with an anti-vibration mounting system. The SPT Heat Shield cools intake air to reduce power loss.For more information, see the SPT Web site© Source: original article on insideline
