Marcos Maniacs

Working on chassis, curious on springs. Removed the shocks and springs from shocks. Front; 12 inch free length, .475 inch wire diameter, 14 coils. Front springs have no give, could probably support a locomotive, probably wrong springs. Online calculate; 252 pound per inch of movement. Rear springs; 12 inch free length, .400 inch wire diameter, 13 coils. Online calculator; 148 pounds per inch of movement. Rear springs had give, could be correct. Question, what springs should a steel chassis Marcos have with a V6? Thank you for the information. Steve V. Marcos in Arizona USA