Swift made Sport Springs keeps the quality ride you get from the showroom, and adds improved handling and lower ride height for driving enthusiasts and style minded drivers who demand only the best.
From HPDE events to SCCA competition, Swift Spec-R Sport Springs are made for the track enthusiast looking to take their vehicle to the next level.
Swift Spec-R Sport Springs were engineered with 3 characteristics in mind.
Modified ride height compared to Sport Springs to maximize optimal suspension geometry.
Further increasing the spring rate to enhance overall performance. The increase in spring rate is based on the upper limits of the vehicles factory shock valving.
Maintaining optimal comfort level for street use.
Spec R springs are wound with the same engineering and material as our sports springs. With the exception of stiffer rates and slight change in ride height; you can expect the same characteristics as our sports springs.
Specifications
BMW E90 335i 2007-2013
Part Number: 4X905R
Front Spring Rate: (224 lb/in) (40 N/mm) (4.0 Kg/mm)
Rear Spring Rate: (616 lb/in) (110 N/mm) (11 Kg/mm)
Front Drop: (1.0") (25mm)
Rear Drop: (0.8") (20mm)
BMW E9X M3 2008-2013
Part Number: 4X903R
Front Spring Rate: (280 lb/in) (50 N/mm) (5.0 Kg/mm)
Rear Spring Rate: (672 lb/in) (120 N/mm) (12 Kg/mm)
Front Drop: (1.0") (25mm)
Rear Drop: (0.7") (18mm)
BMW F30 328i/335i 2014+
Part Number: 4X915R
Front Spring Rate: (251 lb/in) (45 N/mm) (4.5 Kg/mm)
Rear Spring Rate: (605 lb/in) (108 N/mm) (10.8 Kg/mm)
Front Drop: (1.0") (25mm)
Rear Drop: (1.0") (25mm)
BMW F80 M3 2014+
Part Number: 4X909R
Front Spring Rate: (269 lb/in) (48 N/mm) (4.8 Kg/mm)
Rear Spring Rate: (717 lb/in) (128 N/mm) (12.8 Kg/mm)
Front Drop: (1.0") (25mm)
Rear Drop: (0.4") (10mm)
BMW F82 M4 2014+
Part Number: 4X908R
Front Spring Rate: (252 lb/in) (45 N/mm) (4.5 Kg/mm)
Rear Spring Rate: (728 lb/in) (130 N/mm) (13 Kg/mm)
Front Drop: (1.1") (28mm)
Rear Drop: (0.9") (23mm)
BMW E82 135i 2008-2013
Part Number: 4X904R
Front Spring Rate: (201 lb/in) (36 N/mm) (3.6 Kg/mm)
Rear Spring Rate: (504 lb/in) (90 N/mm) (9.0 Kg/mm)
Front Drop: (1.0") (25mm)
Rear Drop: (1.0") (25mm)
