Eibach 1200.250.0900S ERO Coilover Spring 12" x 2.5" ID 900 lb/in Silver

Vehicle Fitment

• Universal - not vehicle-specific; fits any coilover shock or suspension system that accepts a 2.50" inside diameter (64mm) coilover spring in a 12.00" (305mm) free length application
• The 2.50" ID / 12.00" length at 900 lb/in is a high-rate, long-length combination used in demanding performance off-road and race applications including desert racing, stadium off-road, heavy prerunner builds, and purpose-built race vehicles requiring both significant spring force and long shock travel; verify your coilover's spring perch inner diameter and available shock stroke before ordering

Fitment Notes

• Inside diameter (ID): 2.50 inches (64mm) - the most broadly compatible coilover spring bore in the performance and race aftermarket; confirm your coilover's spring perch inner diameter before ordering
• Free length: 12.00 inches (305mm) - a long spring suited to high-travel coilover systems with extended shock bodies or wide perch-to-perch spacing; confirm your coilover's available compression stroke and perch-to-perch mounting distance accommodate a 12.00" free-length spring at the desired installed ride height and preload
• Spring rate: 900 lb/in - a very high rate in the 12.00" x 2.50" ID ERO family; at this rate, the spring is appropriate for heavy race vehicles managing large dynamic loads over long travel ranges, setups requiring very firm spring control to minimize body motion, or applications where a high spring rate is paired with a long free length to maintain adequate travel before block; for context, the 500 lb/in variant in this same length and ID delivers 6.51" of travel; at 900 lb/in the stiffer spring requires more wire per coil and reaches block at 6.40 inches, leaving 5.60 inches of active travel
• Block height: 6.40 inches (163mm) - the spring coils fully solid at this height; the coilover's bump stop must engage well before this point in normal use to protect the shock from bottom-out damage; verify adequate bump stop clearance at full compression; note that the high block height relative to the 12.00" free length reflects the additional wire required to achieve the 900 lb/in rate - stiffer springs inherently have higher block heights at the same free length
• Maximum travel: 5.60 inches (142mm) - from free length to block; while shorter in absolute terms than softer variants at this free length (the 125 lb/in version travels 8.05 inches), 5.60 inches of travel at 900 lb/in with a 5,041-lb block load represents a significant force capacity across a substantial travel range
• Silver powder coat finish - the "S" suffix designates the ERO (Race Off-Road) silver finish; distinguishes ERO springs from the standard red ERS main springs; buyers needing the red ERS finish should order the 1200.250.0900 (no "S" suffix) if available in this rate
• Sold individually - one spring per order; order the quantity required for your specific application

Features

• ERO (Race Off-Road) series - the ERO designation identifies this spring as part of Eibach's off-road-specific product line, engineered for the sustained high-amplitude impacts, high-frequency cycling, and demanding environmental exposure of desert racing, stadium off-road, and high-travel performance off-road builds; the ERO series is built to the surface treatment and construction standards appropriate for off-road duty cycles that impose fundamentally more demanding loading profiles than circuit racing or street use
• 2.50" inside diameter - the most universally compatible coilover spring bore in the performance and race aftermarket; fits the widest range of coilover systems from performance street kits through professional race coilover applications
• 900 lb/in linear rate - among the highest rates available in the 12.00" x 2.50" ID ERO family; the rate is constant throughout the full 5.60-inch active travel stroke, producing predictable, mathematically consistent spring force at every suspension position; at 900 lb/in on a 12.00" spring, the combination is appropriate for vehicles that must manage very high dynamic loads across a long travel range - conditions that typically arise in heavy purpose-built race trucks, vehicles with aggressive suspension geometry requiring high spring rates to achieve target wheel frequencies, or setups where an extremely high spring rate is combined with a long free length to retain travel while maximizing spring force
• High block load of 5,041 lbs - at 900 lb/in over 5.60 inches of travel, the spring generates 5,041 lbs (22,423 N) of force when coiled solid; this is substantially higher than the 3,252-lb block load of the 500 lb/in variant in this same family, reflecting the dramatically higher force capacity of the stiffer spring; the coilover's bump stop must be designed to engage well before this threshold in normal operation
• Shot-peened surface treatment - the spring wire is shot-peened before silver powder coating, introducing compressive residual stress at the wire surface that closes fatigue micro-cracks and dramatically extends service life under repeated high-amplitude impact and high-cycle loading in off-road and race environments
• Preset to block - every Eibach ERO spring is factory-compressed to block before shipment; this eliminates the initial sag that occurs during a new spring's first compression cycles and ensures the rated 12.00" free length and 900 lb/in rate are delivered from the very first installation with no break-in period
• Individually rate-tested - each spring is measured against its rated 900 lb/in value on Eibach's rate testing equipment before leaving the factory; rate consistency is guaranteed, ensuring the installed spring matches the suspension engineer's setup sheet
• Five-Year Warranty - Eibach's warranty covers defects in material and workmanship (other than coatings) when used on passenger cars and light duty (class 1-3) trucks under normal operating conditions
• Silver powder coat finish with imprinted part number - the ERO silver finish provides corrosion resistance against mud, water, dust, and debris in off-road environments; the spring rate and part number are stamped directly on the spring body for correct identification after packaging is removed or springs are mixed in a shop inventory

Specifications

• Part Number: 1200.250.0900S
• Manufacturer: Eibach
• Series: ERO (Eibach Race Off-Road)
• Spring Type: Main coilover spring, linear rate
• Free Length: 12.00 inches (305mm)
• Inside Diameter (ID): 2.50 inches (64mm)
• Spring Rate: 900 lb/in (16.07 kg/mm)
• Block Height: 6.40 inches (163mm)
• Maximum Travel: 5.60 inches (142mm)
• Block Load: 5,041 lbs (22,423 N)
• Weight: 8.60 lbs (3.90 kg)
• Finish: Silver powder coat
• Surface Treatment: Shot-peened
• Preset: Yes - factory preset to block
• Warranty: Five-Year Warranty (material and workmanship defects, coatings excluded)
• Quantity: Sold individually (1 spring)

Included Components

• 1x Eibach ERO Race Off-Road Coilover Spring - 12.00" x 2.50" ID x 900 lb/in (silver)

Product Description

The Eibach 1200.250.0900S is a single ERO (Race Off-Road) series coilover spring - the 12.00-inch free length, 2.50-inch inside diameter, 900 lb/in linear-rate variant from Eibach's off-road coilover spring lineup. At 900 lb/in on a 12.00" free-length spring, this is one of the stiffer rate options in the 2.50" ID family at this length, sitting near the top of the common range that spans 125 to 1,000+ lb/in at 12.00" x 2.50" ID. The "S" suffix designates the silver ERO off-road powder coat finish.

The combination of high rate and long free length serves a specific class of application: vehicles that must manage very high dynamic spring forces - from jump landings, large-amplitude terrain impacts, or heavy aerodynamic or gravitational loads - while simultaneously requiring the extended shock travel that a 12.00" free-length spring enables. At a 6.40-inch block height with 5.60 inches of travel, the spring's working stroke is shorter in absolute terms than softer rate variants at this free length (the 500 lb/in variant delivers 6.51 inches of travel; the 350 lb/in delivers 6.88 inches), reflecting the higher wire content required to achieve the stiffer rate. The 5,041-lb block load is among the highest available in the 12.00" x 2.50" ERO family, providing extremely high spring force capacity throughout the travel range.

Shot peening, factory preset-to-block, individual rate testing, and the Five-Year Warranty (excluding coatings) are standard. The spring rate and dimensions are stamped on the silver powder-coated body for shop identification. Sold individually.