Balanced daily comfort with real back-road capability.
Designed to lower your 355 by approximately 25–40 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 –1994–1999 Ferrari F355 (F129)
Precision-tuned for the mid-engine legend:
The Dežru Suspension Spec-S system brings modern damper technology to one of Ferrari’s most iconic chassis—the F355 (F129). Engineered for precision and feel, the Spec-S transforms the driving dynamics of the 355 without sacrificing the purity that defines it.
Developed through extensive road and circuit testing, each Spec-S kit features digressive monotube dampers, precision CNC-machined hardware, and spring rates matched to the F355’s weight distribution and motion ratios. The result is a balance of razor-sharp response, improved ride control, and authentic Ferrari feedback—refined for today’s performance expectations.
Key Features
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Adjustable damping for fine-tuning compression and rebound balance.
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Monotube digressive valving ensures firm, predictable chassis control with supple low-speed compliance.
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Linear HyperCoil springs chosen to complement the F355’s suspension geometry and mid-engine balance.
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Hand-built and dyno-tested to ensure matched damping curves across all four corners.
F355 "Challenge" option shock dyno test shown
Why We Use a 225 / 325 Spring Rate on the F355
The Ferrari F355 is extremely sensitive to suspension changes. Mid-engine weight distribution, short wheelbase, and aggressive factory geometry mean small changes in spring rate have a large impact on both balance and drivability.
The OEM setup is relatively soft, particularly at the front, which prioritizes ride quality but allows excess pitch, roll, and reliance on bump stops when the car is driven hard or lowered. Once ride height is reduced by ~40 mm, available bump travel is significantly decreased, and the factory spring rates no longer provide adequate support.
Our 225 lb/in front and 325 lb/in rear configuration is specifically chosen to address this without compromising the character of the car.
At the front, 225 lb/in increases wheel rate enough to:
- reduce dive under braking
- improve steering response and front-end support
- maintain compliance over imperfect road surfaces
At the rear, 325 lb/in maintains proper platform control for a mid-engine layout by:
- supporting rear weight bias without excessive squat
- stabilizing the chassis during throttle transitions
- preserving traction while preventing the “float” common with softer rear rates
Just as important, this combination maintains the correct front-to-rear balance. The ratio is not arbitrary. It is selected to keep the car neutral and predictable at the limit, avoiding both front-end push and rear instability.
This setup is firm enough to support aggressive street driving and canyon use, yet compliant enough to remain comfortable on real roads. It is not a track-only rate, nor is it a softened compromise. It is a properly engineered balance between control and usability.
As with all Dežru systems, the dampers are valved specifically for this spring combination. A spring rate alone does not define performance. The relationship between spring force, damping curve, and available travel is what determines how the car actually behaves.
This is not guesswork. It is a matched system.
Why Choose Dežru Spec-S
The F355 rewards finesse, and the Spec-S delivers the perfect chassis harmony to unlock it. Expect heightened confidence, a more connected steering feel, and flat, predictable cornering—all while maintaining the car’s unmistakable analog character.
