Good Parts front springs offer both increased stiffness and lower ride height compared to factory TR6 front springs. Spring rate is 390 lb/in compared to the approximately 305 lb/in. of the stock springs. Ride height is approximately 14-14 ½ inches from the center of the wheel to the fender edge, which is roughly 1” lower than factory spec springs. Ride height can be increased with Good Parts aluminum spring spacers. Spring free length is approximately 8⅞ inches.
Using these springs in a TR4A will require a spacer. The size of the spacer will be determined by the desired ride height.
Springs will often settle slightly during initial use. Taking a short drive or rolling the car back and forth on a flat surface after installation will allow the springs to settle into place before final ride height measurements are taken.