When running the QA1 OED7855P, RC7855P or DOE7855P front coil-over shocks we recommend the following QA1 front spring rates:
275# springs: A lightweight (< 3,000 lbs.) drag only car
300# springs: A full weight (> 3,000 lbs.) street/strip car
325# springs: A full weight (> 3,000 lbs.) street car wanting good handling