Swift Rear Coil Spring - Tight Helix - 5.0" O.D. x 13" Tall - 225 lb. SC02301 They are 100% dyno tested

They are 100% dyno tested and serialized and serviceable and rebuildable by QA1 authorized service centers

Every assembly is balanced at the factory to precise tolerances

Chevrolet 454/502 90-up external balance 168 tooth

900 in Rectangular Port

Swift Rear Coil Spring - Tight Helix - 5.0" O.D. x 13" Tall - 225 lb. SC02301 They are 100% dyno testedINCREASE TRACTION, LESS UN SPRUNG MASS, MORE STROKE, INCREASED HANDLING. THE ONLY THING YOU WILL BE LOSING IS TRACK TIME. Swift Springs manufactures springs with differing rates for a variety of circle track racing applications. With options for both dirt and asphalt tracks, Swift has a wide range of coil spring formats, including coil over, dual rate, bump springs, and more. Swift Springs superior engineering has provided the next generation of