UMI Performance AB7550-1 Double Adjustable Coilover Lowering Kit with Viking Shocks

The UMI Performance AB7550-1 is a complete coilover adjustable spring lowering kit featuring four Viking double adjustable shocks paired with a hybrid front coilover spring system and rear lowering springs. Designed as a true bolt-in solution, this kit requires no welding and — uniquely — no spring compressor for front installation. Whether you're tuning for street cruising, drag racing, or corner carving, the AB7550-1 gives you full control over ride height and suspension character.

Shock & Damping Features:

• (2) Front coilover shocks — double adjustable, hand-built in Lakeville, Minnesota
• (2) Rear shocks — double adjustable, hand-built in Lakeville, Minnesota
• 19 independent compression settings and 19 independent rebound settings per shock
• Adjust from street to strip to corner carving with a simple knob turn — no tools required
• Recommended baseline settings: Street — 6C/8R all around; Corner carving — 10C/12R all around; Strip — 6C/2R front, 6C/6R rear

Spring Specifications:

• (2) Front springs — choose from 250, 350, 450, or 550 lb/in spring rate
• 250 lb — 11" tall drag-race-only springs; serious weight reduction required
• 350 lb — Drag race or street cruise with weight reduction recommended
• 450 lb — Small block street cruise or big block drag race
• 550 lb — Small block performance handling or all big block applications except drag
• (2) Rear springs — available with 1" or 2" drop
• Viking premium USA-made springs, shot-peened and coated for long-term durability

Ride Height & Handling:

• 0–3" front lowering range via the hybrid coilover system
• 1" or 2" rear drop choice for factory-level or Pro-Tour stance
• Lower center of gravity improves handling and places the upper A-arm in a more favorable geometry
• Easy front height adjustment — compatible with optional Torrington (thrust) bearing kit and spanner wrench

Optional Spanner Wrench & Thrust Bearing Kit: The spanner wrench allows ride height adjustment while the shock remains mounted. The thrust bearing kit sits between the spring and the spring seat, allowing the seat to rotate on a bearing for smoother, easier height changes. This accessory is strongly recommended for all adjustments but is not required for installation.

Shocks are hand-assembled in the USA, and the entire package is engineered to deliver a balance of performance, adjustability, and long-term reliability — all without the complexity of a full coilover conversion.