1971 CHEVROLET SPRING CHART SUPPLEMENT FRONT VEHICLE HEIGHT ADJUSTMENT RANGE PART NO WEIGHT CHANGE INCHES A 3991239 0 3991241 80 3991242 1 20 3991243 1 60 3991244 2 00 3891250 0 3991251 41 3991252 82 3991253 1 23 3991254 1 64 3991255 2 05 REAR VEHICLE HEIGHT ADJUSTMENT RANGE PART NO HEIGHT CHANGE INCHES C 482065 0 482067 88 D 482090 66 482152 1 00 E 482696 0 482698 50 In using the above supplementary spring chart it should be noted that for each rate range the lowest spring load value is set at zero inches change for reference The increasing order of load value in each range will then show the vehicle height increase which can be achieved when selecting the next higher load range spring