Adrian Venn who used to have a TVR shop in England published a bunch of suspension data that is posted on the TVRCCNA web site. In it he lists the spring rates as: Front 135 lb/in, Rear 140 lb/in. The front number looks extremely low. I replaced my shocks with GAZ adjustable coil-overs. I used 250 lb/in for front sprigs and 180 lb/in for the rear. Seem to work quite nicely. Ride is not harsh or jiggly. Handles better than it ever did but that may be because the original Armstrong shocks weren't very good and I am riding on new (classic series) Pirelli CN36 (205/70 - 14) tires and new Superflex Polyurethane bushings all around.