Balanced daily comfort with real back-road capability.
Designed to lower your car by approximately 25–30 mm while maintaining composure over real-world roads, the Spec-S sharpens turn-in and body control without beating you up on the commute.
Dežru Spec-S Coilovers – BMW E90 3-Series (2005–2013)
The Dežru Spec-S coilover system is engineered specifically for the BMW E90 3-Series, a well-balanced rear-wheel-drive chassis that rewards precise damping and correctly matched spring rates. Designed around the E90’s near 50/50 weight distribution, suspension geometry, and dual-purpose nature, the Spec-S delivers improved body control, sharper turn-in, and greater confidence without sacrificing daily comfort.
Developed for drivers who daily their E90 but still enjoy spirited street driving, canyon roads, and occasional HPDE track days, the Spec-S features digressive piston valving that provides strong low-speed support during braking, turn-in, and transitions, while remaining compliant over rough pavement and surface imperfections. Rather than chasing extreme stiffness, this setup targets a balanced ride frequency in the ~2.0–2.3 Hz range, tightening the platform while keeping the car refined and livable.
Fixed-length damper bodies paired with a 25–35 mm adjustable lowered ride height ensure proper suspension stroke and geometry are preserved. This maintains usable bump travel and predictable roll behavior, allowing the E90 to remain composed, stable, and confidence-inspiring during both daily driving and aggressive use.
Key Features
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Digressive monotube dampers for controlled body motion, consistent damping performance, and clear driver feedback.
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Fixed-length damper bodies with 25–35 mm adjustable lowered ride height to preserve suspension geometry and usable travel.
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Adjustable damping to fine-tune rebound for daily driving, back-road use, or HPDE track events.
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550 lb/in front and 700 lb/in rear spring rates, selected to reduce body roll, improve turn-in, and maintain rear traction without introducing harshness.
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Linear HyperCoil springs for predictable load transfer and smooth, consistent response throughout suspension travel.
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OEM-style upper mounts to minimize NVH while maintaining proper fitment and alignment consistency.
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Hand-built, dyno-matched pairs to ensure precise left-to-right damping consistency.

Performance Character
The Spec-S transforms the BMW E90 by significantly reducing excess body motion and sharpening overall chassis response while retaining the refinement expected from a BMW sport sedan. The digressive damping profile provides immediate support during initial inputs and transitions, paired with controlled compliance that keeps the tires planted as grip levels increase.
The result is an E90 that feels planted, predictable, and confidence-inspiring, remaining comfortable for daily driving while delivering the control and precision needed for aggressive street and track use.