Stock Spring Rates
Model/Year Front Spring Rate (lb/in) Rear Spring Rate (lb/in)
Mustang GT/V6 Coupe 1994-2004 450 (linear) 210 (linear, solid axle)
Mustang GT/V6 Vert. 1994-2004 400 (linear) 185 (linear, solid axle)
Mustang Cobra Coupe 1999-2001 500 (linear) 475 (linear, IRS)
Mustang Cobra Coupe 2003-2004 600 (linear) 600 (linear, IRS)
Mustang Cobra Vert. 2003-2004 500 (linear) 470 (linear, IRS)
Mustang Cobra R 2000 800 (linear) 750 (linear, IRS)
Mustang Mach1 Coupe 2003-2004 600 (linear) 250 (linear, solid axle)
Mustang Bullitt Coupe 2001-20022 600 (linear) 250 (linear, solid axle)
Aftermarket Spring Rates
Manufacturer/Part Info Front Spring Rate (lb/in) Rear Spring Rate (lb/in)
Ford Racing B Springs (M5300B) 425-530 (progressive) 200-300 (progressive, solid axle)
Ford Racing C Springs (M5300C) 650 (linear) 200-300 (progressive, solid axle)
Ford Racing F Springs (M5300F) 460-570 (progressive) 170-310 (progressive, solid axle)
Ford Racing G Springs (M5300G) 500-570 (progressive) 170-310 (progressive, solid axle)
Ford Racing R Springs (M5300R) 700-850 (progressive) 200-260 (progressive, solid axle)
Eibach Pro-Kit Springs (94-04 Mustangs) 425-530 (progressive) 200-300 (progressive, solid axle)
Eibach Race Kit Springs(94-04 Mustangs) 700-850 (progressive) 200-260 (progressive, solid axle)
Eibach Sportline Springs (79-04 Mustangs) 425-630 (progressive) 140-295 (progressive, solid axle)
H&R Sport Springs (94-04 Mustangs) 490-575 (progressive) 205-250 (progressive, solid axle)
H&R Sport Springs (99-04 Cobra) 700-760 (progressive) 685 (linear, IRS)
H&R Super Sport Springs (94-04 Mustangs) 700-760 (progressive) 275-300 (progressive, solid axle)
H&R Race Springs (79-04 Mustangs) 750-850 (progressive) 260-280 (progressive, solid axle)
H&R Race Springs (99-04 Cobra) 750-850 (progressive) 770 (linear, IRS)
Progress Springs (94-04 Mustangs) 580 (linear) 250-300 (progressive, solid axle)
Steeda Sport Springs (79-04 Mustangs) 650 (linear) 200-250 (progressive, solid axle)
Steeda Sport Springs (03-04 Cobra) 720-780 (progressive) 650-790 (progressive, IRS)
Steeda Competition Springs (79-04 Mustangs) 750-850 (progressive) 250 (linear, solid axle)
Steeda Full Competition Springs (front only) (94-04 Mustangs) 850-1050(progressive)
StangSuspension Springs (94-04 Mustangs) 490-575 (progressive) 205-250 (progressive, solid axle)
Model/Year Front Spring Rate (lb/in) Rear Spring Rate (lb/in)
Mustang GT/V6 Coupe 1994-2004 450 (linear) 210 (linear, solid axle)
Mustang GT/V6 Vert. 1994-2004 400 (linear) 185 (linear, solid axle)
Mustang Cobra Coupe 1999-2001 500 (linear) 475 (linear, IRS)
Mustang Cobra Coupe 2003-2004 600 (linear) 600 (linear, IRS)
Mustang Cobra Vert. 2003-2004 500 (linear) 470 (linear, IRS)
Mustang Cobra R 2000 800 (linear) 750 (linear, IRS)
Mustang Mach1 Coupe 2003-2004 600 (linear) 250 (linear, solid axle)
Mustang Bullitt Coupe 2001-20022 600 (linear) 250 (linear, solid axle)
Aftermarket Spring Rates
Manufacturer/Part Info Front Spring Rate (lb/in) Rear Spring Rate (lb/in)
Ford Racing B Springs (M5300B) 425-530 (progressive) 200-300 (progressive, solid axle)
Ford Racing C Springs (M5300C) 650 (linear) 200-300 (progressive, solid axle)
Ford Racing F Springs (M5300F) 460-570 (progressive) 170-310 (progressive, solid axle)
Ford Racing G Springs (M5300G) 500-570 (progressive) 170-310 (progressive, solid axle)
Ford Racing R Springs (M5300R) 700-850 (progressive) 200-260 (progressive, solid axle)
Eibach Pro-Kit Springs (94-04 Mustangs) 425-530 (progressive) 200-300 (progressive, solid axle)
Eibach Race Kit Springs(94-04 Mustangs) 700-850 (progressive) 200-260 (progressive, solid axle)
Eibach Sportline Springs (79-04 Mustangs) 425-630 (progressive) 140-295 (progressive, solid axle)
H&R Sport Springs (94-04 Mustangs) 490-575 (progressive) 205-250 (progressive, solid axle)
H&R Sport Springs (99-04 Cobra) 700-760 (progressive) 685 (linear, IRS)
H&R Super Sport Springs (94-04 Mustangs) 700-760 (progressive) 275-300 (progressive, solid axle)
H&R Race Springs (79-04 Mustangs) 750-850 (progressive) 260-280 (progressive, solid axle)
H&R Race Springs (99-04 Cobra) 750-850 (progressive) 770 (linear, IRS)
Progress Springs (94-04 Mustangs) 580 (linear) 250-300 (progressive, solid axle)
Steeda Sport Springs (79-04 Mustangs) 650 (linear) 200-250 (progressive, solid axle)
Steeda Sport Springs (03-04 Cobra) 720-780 (progressive) 650-790 (progressive, IRS)
Steeda Competition Springs (79-04 Mustangs) 750-850 (progressive) 250 (linear, solid axle)
Steeda Full Competition Springs (front only) (94-04 Mustangs) 850-1050(progressive)
StangSuspension Springs (94-04 Mustangs) 490-575 (progressive) 205-250 (progressive, solid axle)