Track Spring This RFQ was sourced on www.MFG.com in USA for Coil Springs Please quote the following two springs: A front Coil spring for the Ford Mustang, with a progressive rate of 700 - 850 lbs. A rear Coil Spring for the Ford Mustang, with a progressive rate of 350 - 390 lbs. We want about 1 1/4 to 1 1/2" drop. The quantities listed above apply to each configuration, so (20, 40, 80) Buyer Information Industry Automotive City/Region Doylestown, Pennsylvania Country USA RFQ RFQ Number 338169 Material Alloy Steel Technical Specifications Category Coil Springs Dimensions Get quotes online for manufacturing services at MFG.com from machine shops, fabricators, job shops and contract manufacturers. MFG.com connects buyers and suppliers when the buyer has a need and the supplier has the right expertise and capacity. MFG.com analyzes all engineered parts and RFQs for improved manufacturability and to ensure quality and a quick quoting experience. Coil Springs: Springs are mechanical devices, commonly made from tensioned steel, used to exert pressure or tension, resist tension, or retract after tension is applied. Springs can be flat or coiled.