{"product_id":"performance-muffler-cover-fits-stihl-066-660-650","title":"Performance Muffler Cover – Fits Stihl 661","description":"\u003cp\u003e \u003c\/p\u003e\n\u003cp class=\"MsoNormal\" style=\"text-align: center;\"\u003e\u003cb\u003eAerospace-Grade Performance Exhaust System for STIHL MS 661\u003c\/b\u003e\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eEnhance power and improve engine cooling with this precision-engineered exhaust system designed for the STIHL MS 661. Made from lightweight 6061 T6 billet aluminum, a high-strength aerospace alloy known for excellent heat dissipation, the one-piece muffler cover optimizes exhaust flow while helping to keep your engine cooler and extend component life.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003eProudly manufactured in the USA and backed by a lifetime warranty, this exhaust system delivers lasting durability under demanding conditions.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eOutlet Direction (Facing Bar or Facing Recoil):\u003c\/b\u003e\u003ci\u003eFacing Bar\u003c\/i\u003e means the exhaust outlet points toward the guide bar side of the saw. \u003ci\u003eFacing Recoil\u003c\/i\u003e means it points toward the pull-start side. This is strictly operator preference and has no effect on performance.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eCompatible Models:\u003c\/b\u003e\u003cbr\u003eSTIHL MS 661\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eIncludes:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul style=\"margin-top: 0in;\" type=\"disc\"\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo2; tab-stops: list .5in;\"\u003eOne-piece muffler cover CNC machined from 6061 T6 billet aluminum\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo2; tab-stops: list .5in;\"\u003eSpark arrestor screen with aperture size compliant with USFS specifications\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo2; tab-stops: list .5in;\"\u003eHigh-Temperature Gasket – Made in the USA\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l2 level1 lfo2; tab-stops: list .5in;\"\u003eLonger top screws with vibration-resistant Belleville washers\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eDyno Proven Performance\u003c\/b\u003e\u003cbr\u003eTested on a completely stock saw with no modifications other than the muffler cover. Results showed a 6.21% increase in horsepower, and a 9.92% increase in torque. Performance gains will vary depending on the saw and the level of modification.\u003c\/p\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eInstallation Notes:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul style=\"margin-top: 0in;\" type=\"disc\"\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo3; tab-stops: list .5in;\"\u003eApply thread locker on all mounting screws for secure, vibration-resistant assembly\u003c\/li\u003e\n\u003cli class=\"MsoNormal\" style=\"mso-list: l1 level1 lfo3; tab-stops: list .5in;\"\u003ePost-installation tuning or recalibration is required for optimal performance\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"MsoNormal\"\u003e\u003cb\u003eWarranty\u003c\/b\u003e\u003cbr\u003eLifetime warranty covers defects in materials and workmanship under normal use. Excludes misuse, neglect, or unauthorized modifications.\u003c\/p\u003e","brand":"Undaunted Manufacturing","offers":[{"title":"Facing Bar","offer_id":51389236379959,"sku":"PERFORMANCE_MUFFLER_COVER_FITS_STIHL_661_FACING_BAR","price":95.0,"currency_code":"USD","in_stock":true},{"title":"Facing Recoil","offer_id":51389236412727,"sku":"PERFORMANCE_MUFFLER_COVER_FITS_STIHL_661_FACING_RECOIL","price":95.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0965\/4570\/2199\/files\/IMG_5925.jpg?v=1764097705","url":"https:\/\/undauntedmfg.com\/products\/performance-muffler-cover-fits-stihl-066-660-650","provider":"Undaunted Manufacturing","version":"1.0","type":"link"}