Spring load at 1.67" 105lbs Spring load at 1.120" 270lbs Spring rate 300 lbs per inch Coil bind 1.060. Performance 550 lift beehive valve springs for the 3V Ford heads. Drop in replacement, no machining necessary. Fits stock retainers and seats. The item "CMS 3V Valve Spring Kit.550 lift" is in sale since Thursday, September 20, 2018. This item is in the category "eBay Motors\Parts & Accessories\Car & Truck Parts\Engines & Components\Camshafts, Lifters & Parts". The seller is "sbc_svt" and is located in Huntley, Illinois. This item can be shipped to United States, Canada.