Tag: spring rate

Dear Welder Series… coil over questions

Dear Welder Series…
Hi, I intend to order the frame rails and body next month, and I am sorting parts lists.  One question for a coil over kit. What will the normal coil over length at ride height and what spring rate works with a Hi boy, I have a sbf and a bbf, and will open up the bbf to see if it is rebuidable soon. ? Any mfg. recommended?


Dear Sherman…
Sherman, a good coil-over ride height is 13″.  Several companies have coil-overs with an open dimension of about 14-1/2″ and a closed dimension of about 10″.  It would be best to ask the coil-over people about spring rates.  Some have progressive would springs, others have linear rates.  An example a 200 pound linear rate is that it takes 200 lbs to compress the spring 1″ and 400 lbs to compress the spring 2″.  A progressive wound rate would be that it takes 200 lbs to compress 1″ and possible 500 lbs to compress the spring 2″.  The rate you will want will depend on many factors:  actual weight on the rear, shock mounting angle, ride quality that you want, etc.  Heidt’s, QA1, Aldan, and Total Cost Involved are good sources.