Product Summary

6.78" Outside Diameter, 18.1 SFI Rating, Aluminum

  • Elastomer construction with SFI 18.1 approval for performance engine use
  • Internally balanced design for GM LS-series applications (LS1/LS2 F/V-body fitment)
  • 6.78" diameter with 360-degree timing marks for easy, accurate setup and verification
  • Integrated drive features: outer 6-rib serpentine pulley plus included 25-tooth HTD (8 mm pitch) pulley
  • 10% underdrive and robust materials (steel hub / aluminum shell) in a black oxide finish for strength and longevity
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Key Specs

MFG. Part #918855
Outside Diameter6.78"
Material TypeAluminum
FinishBlack Oxide
SFI RatedYes
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Need To Know

Quick and Easy Returns

Return Policy

ATI 918855 Details

The ATI 918855 Super Damper harmonic balancer is an SFI 18.1–approved, elastomer-style damper built for internally balanced GM LS-series applications, including LS1/LS2 F- and V-body setups. With a 6.78" OD and a total weight of 6.75 lbs, it combines a steel hub with an aluminum hub shell and a black oxide finish for a durable, performance-ready package. It features 360-degree timing marks, a single 0.188" keyway, an outer 6-rib serpentine pulley, and an included HTD pulley (25-tooth, 8 mm pitch) with a 10% underdrive to help optimize accessory drive speed while maintaining dependable torsional control.

  • Elastomer construction with SFI 18.1 approval for performance engine use
  • Internally balanced design for GM LS-series applications (LS1/LS2 F/V-body fitment)
  • 6.78" diameter with 360-degree timing marks for easy, accurate setup and verification
  • Integrated drive features: outer 6-rib serpentine pulley plus included 25-tooth HTD (8 mm pitch) pulley
  • 10% underdrive and robust materials (steel hub / aluminum shell) in a black oxide finish for strength and longevity

CARB Warning

For race/ off road use or for use on pre-1966 vehicles.

Emissions warning: this part only legal for sale or use in California for racing (competition) vehicles which may never be used, registered, or licensed for use upon a public highway, or if installed in vehicles model-year 1965 or older; motorcycles model-year 1977 or older; or off-highway recreational vehicles (such as off-road motorcycles and all-terrain vehicles) model-year 1996 and older. Any other use renders the vehicle tampered and not legal for use on California public highways (any public street or roadway, public dirt road, public park, or publicly maintained right of way open to the use of the public for vehicular travel). Violations subject to $37,500 penalty per violation per vehicle, revocation of registration, loss of use on California public right of ways, and proof of correction for tampering. There are similar restrictions and penalties under federal law and the laws of all other states with penalties under federal law of up to approximately $45,268 per tampered vehicle and/or engine.

ATI 918855 Specifications

KEY SPECS
MFG. Part #918855
BrandATI
Outside Diameter6.78"
Material TypeAluminum
FinishBlack Oxide
SFI RatedYes
GENERAL
SFI Rating18.1
Weight6.75 lbs
Sold in QuantityEach
Hardware IncludedYes
Degree MarkingsYes
Harmonic Balancer ConstructionElastomer

Questions & Answers

Fitment

  • GM LS6

  • GM LS2

  • GM L76

  • GM LS1

  • GM LS1

  • GM LS1

  • GM LS6

  • GM LS2

  • GM L98

  • GM L98

  • GM L98

  • GM L98

  • GM L98

  • GM L98

  • GM LZ1

  • GM L77

  • GM L96

  • GM LZ1

  • GM LS2

  • GM LZ1

  • GM L96

  • GM L96

  • GM L96

  • GM L96

  • GM LZ1

  • GM L96

  • GM L96

  • GM LS1

  • GM LS1

  • GM LS2

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