Eibach 0700.225.0850 ERS Linear Coilover Spring 7" x 2.25" ID 850 lb/in Red

Vehicle Fitment

• Universal - not vehicle-specific; fits any coilover shock or suspension system that accepts a 2.25" inside diameter (57mm) coilover spring in a 7.00" (178mm) free length application
• The 2.25" ID / 7.00" length combination is widely used in motorsport coilover systems including Formula car, open-wheel single-seater, road racing, autocross, hillclimb, and drift applications that use compact, narrow-body coilover shocks with smaller-diameter spring perches; verify your coilover's spring perch inner diameter and available stroke before ordering

Fitment Notes

• Inside diameter (ID): 2.25 inches (57mm) - this is a small-bore spring ID used in coilover systems with narrow shock bodies or where minimizing unsprung weight is critical; it is narrower than the more common 2.50" coilover spring ID and will not properly seat on a 2.50" perch; measure your coilover's spring seat inner diameter before ordering
• Free length: 7.00 inches (178mm) - confirm your coilover's available shock stroke and perch-to-perch mounting distance accommodate a 7.00" free-length spring at the desired installed ride height and preload setting
• Spring rate: 850 lb/in - a very high rate for a street or light competition coilover; at 850 lb/in, this spring is appropriate for race applications where low suspension compliance is required and where high spring rates are necessary to control body motion at racing speeds, manage aerodynamic downforce loads, or compensate for stiff suspension geometry; it is also appropriate for front coilover use on certain high-grip autocross cars or vehicles with stiff supporting damping
• This is a main coilover spring (not a tender/helper spring) - it is intended to be the primary load-bearing spring in the coilover; it can be used as a standalone spring or as the primary element in a dual-spring configuration with a softer tender spring
• Sold individually - one spring per order; most coilover applications require one spring per corner; order the quantity required for your build (two for a single axle, four for a full vehicle installation)

Features

• ERS (Eibach Race Spring) standard main spring - the ERS designation identifies this as a spring from Eibach's core race spring catalog, their most widely used product line across all forms of motorsport; ERS main springs are the standard in Formula 1, WRC, Le Mans, NASCAR, and virtually every major international race series where spring selection is an engineered decision; the red powder coat finish is the universal ERS main spring identifier
• 2.25" inside diameter - the smallest standard ID in Eibach's ERS main spring family; the narrower bore results in a smaller spring cross-section for a given rate, producing lower weight and smaller installed diameter; this makes 2.25" ID springs the preferred choice in formula car and single-seater applications where unsprung weight minimization and compact coilover geometry are design priorities
• 850 lb/in high-rate linear spring - at 850 lb/in, this is among the higher rate springs in the 7.00" length / 2.25" ID family; high spring rates are used where: aerodynamic downforce must be managed at circuit speeds; wheel frequency requirements for specific handling balance demand stiff springs; ground clearance must be tightly controlled; or a stiffer primary spring is combined with a very soft tender to create a wide dual-spring system rate range; the rate is linear throughout the full compression stroke, ensuring consistent, predictable response at every point of travel
• Ultra-lightweight for reduced unsprung mass - Eibach engineers the 2.25" ID spring wire cross-section to the minimum required to achieve the rated spring rate using their Super Hi-Ten spring steel alloy; reducing the unsprung mass at each corner improves wheel contact patch fidelity and high-frequency response to track surface irregularities - a measurable performance benefit in both race and high-performance street applications
• Minimum block height, maximum travel - Eibach's winding geometry minimizes the ratio of block height to free length; this maximizes the spring's useful travel before coiling solid, giving the suspension engineer maximum working range within the shock's available stroke
• Shot-peened surface treatment - every ERS spring wire is shot-peened before finish coating; shot peening introduces compressive residual stress at the wire surface, closing fatigue-initiating surface micro-cracks and dramatically extending service life under the high-cycle loading of race environments
• Preset to block - every Eibach ERS spring is factory-compressed to block before shipment, eliminating the initial sag that causes a new spring's effective rate and free length to shift during the first compression cycles; the rated free length and rate are delivered from the first installation with no break-in period
• Individually rate-tested - each spring is tested against its rated 850 lb/in value on Eibach's measurement equipment before leaving the factory, guaranteeing the spring rate matches the setup sheet specification
• Red powder coat finish with imprinted part number - the red finish is the universal ERS main spring color identifier; the spring rate and dimensions are stamped on the spring body for identification after packaging has been removed or springs have been mixed in a shop inventory

Specifications

• Part Number: 0700.225.0850
• Manufacturer: Eibach
• Series: ERS (Eibach Race Spring) - Standard Main Spring
• Spring Type: Main coilover spring, linear rate
• Free Length: 7.00 inches (178mm)
• Inside Diameter (ID): 2.25 inches (57mm)
• Spring Rate: 850 lb/in (15.17 kg/mm / 149 N/mm)
• Finish: Red powder coat
• Surface Treatment: Shot-peened
• Preset: Yes - factory preset to block
• Weight: 4.4 lbs
• Quantity: Sold individually (1 spring)

Included Components

• 1x Eibach ERS Linear Main Coilover Spring - 7.00" x 2.25" ID x 850 lb/in (red)

Product Description

The Eibach 0700.225.0850 is a single ERS Linear Main Coilover Spring - the 7.00-inch free length, 2.25-inch inside diameter, 850 lb/in variant from Eibach's core Race Spring System. The ERS line is the standard reference in professional motorsport spring selection globally, used across Formula 1, WRC, Le Mans/GT, NASCAR, IndyCar, and virtually every other major series where spring rate and spring consistency are engineered parameters rather than off-the-shelf estimates.

The 2.25-inch inside diameter is the smallest standard ID in Eibach's ERS main spring catalog, developed specifically for the narrow-body coilover shocks used in formula cars, single-seaters, and lightweight race builds where minimizing unsprung mass is a measured performance objective. At 850 lb/in across a 7.00-inch free length, this spring occupies the high end of the rate range for this ID family - appropriate for applications managing aerodynamic downforce loads at circuit speeds, vehicles with extremely stiff suspension geometry requiring high spring rates to maintain desired wheel frequencies, or front coilover setups on high-grip autocross cars where body motion control and consistent ground clearance take priority over ride compliance.

As with every Eibach ERS spring, the wire is shot-peened before coating to compressively stress the surface and eliminate fatigue micro-cracks, the spring is preset to block at the factory to remove initial sag, and each unit is individually rate-tested before shipment. The red powder coat finish identifies it as an ERS main spring; the part number and dimensions are stamped on the spring body for identification outside of packaging. Weight is 4.4 lbs. Sold individually.