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QA1

QA1 GS401-10550C Front Pro Coil Single Adj Coilover Kit Full Size GM 550 lb/in

Regular price
$749.95
Regular price
$830.83
Sale price
$749.95
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In Stock: 4

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Product Specification:

SKU:QAPGS401-10550C

MPN: GS401-10550C

UPC: 806990062185

Weight: 23.9 lb

Inventory: 4

Type: Coilovers



Description

Vehicle Fitment

  • 1971-1996 Chevrolet Impala, Caprice, Bel Air (GM Full-Size / B-Body / C-Body)
  • 1977-1993 Chevrolet Caprice, Impala (GM B-Body)
  • 1971-1996 Buick LeSabre, Electra, Estate Wagon (GM Full-Size)
  • 1971-1996 Oldsmobile Delta 88, 98, Custom Cruiser (GM Full-Size)
  • 1971-1996 Pontiac Bonneville, Catalina, Parisienne (GM Full-Size)
  • 1978-1988 GM G-Body (Monte Carlo, Malibu, El Camino, Regal, Cutlass, Grand Prix) - with compatible spring perch geometry
  • Compatible Ford full-size vehicles and Galaxies with equivalent front suspension geometry

Fitment Notes

  • Bolt-in compatible with both factory OE stamped steel control arms and QA1 tubular control arms - no control arm replacement required
  • Upper mount: Stud type / Lower mount: Bar pin (T-bar type)
  • Some applications may require the lower A-arm to be dropped for installation; shock body diameter may require enlarging the lower control arm shock opening
  • Provides 0 to -2 inches of front ride height adjustability
  • 550 lbs/in is a stiffer spring rate suited for heavier front axle weight full-size GM builds (approximately 2,001-2,100 lbs); for lighter builds see the 450 lbs/in kit (GS401-10450C or GD507-10450C); contact QA1 tech support for spring rate guidance
  • Spring style: 10-inch tapered Style C (large diameter flat upper) - specific to full-size GM spring perch geometry
  • Register shocks at QA1 before installation to activate Limited Lifetime Warranty

Features

  • Single adjustable GS401 Pro Coil shock - 18 valving positions of simultaneous compression and rebound adjustment for easy on-car tuning
  • Provides 0 to -2 inches of front ride height adjustability via threaded shock body spring seat nut
  • Includes a 10-inch tapered Style C high travel chrome silicon spring at 550 lbs/in - stiffer rate for heavier full-size GM builds requiring more front spring support
  • Fewer coils and smaller wire diameter vs. conventional springs for increased travel and reduced unsprung weight
  • Bolt-in with both factory OE and QA1 tubular control arms for maximum build flexibility
  • Stud upper / bar pin T-bar lower mount configuration for stock-style full-size GM front suspension integration
  • Suitable for street performance, autocross, road racing, drag racing, and street rod applications
  • 100% dyno-tested and serialized for verified, consistent performance
  • Serviceable and rebuildable by QA1 Authorized Service Centers
  • Made in the USA at QA1's Lakeville, Minnesota facility

Specifications

  • Part Number: GS401-10550C
  • Type: Front Pro Coil Single Adjustable Coilover System
  • Application: 1971-1996 GM Full-Size / B-Body / C-Body; 1978-1988 GM G-Body; Compatible Ford Full-Size
  • Shock Model: GS401 Single Adjustable Pro Coil
  • Valving: 18 positions (simultaneous compression and rebound)
  • Spring Length: 10 inches (tapered, Style C - large diameter flat upper)
  • Spring Rate: 550 lbs/in
  • Spring Material: Chrome Silicon High Travel
  • Ride Height Adjustability: 0 to -2 inches
  • Upper Mount: Stud Type
  • Lower Mount: Bar Pin (T-Bar Type)
  • Warranty: Limited Lifetime (register before installation)
  • Quantity: Pair (2 shocks + 2 springs)
  • Made in the USA

Included Components

  • 2x QA1 GS401 Single Adjustable Pro Coil Front Shocks (100% Dyno-Tested and Serialized)
  • 2x 10-Inch Tapered Style C High Travel Chrome Silicon Springs - 550 lbs/in
  • 1x Complete Hardware Kit (all required mounting hardware)

Product Description

The QA1 GS401-10550C is a single adjustable front Pro Coil coilover system engineered as a bolt-in front suspension upgrade for 1971-1996 GM full-size vehicles - including the Impala, Caprice, Buick LeSabre, Oldsmobile 88, and Pontiac Bonneville - as well as compatible 1978-1988 GM G-Body applications and Ford full-size vehicles and Galaxies with equivalent front suspension geometry. This kit replaces the factory front coil spring and shock with an adjustable coilover assembly that provides up to 2 inches of ride height drop and 18 simultaneous compression and rebound valving positions for easy, on-car front suspension tuning.

At 550 lbs/in, this spring rate is the stiffer option in the full-size GM Pro Coil lineup, targeted at heavier builds where the 450 lbs/in rate would be insufficient. The 10-inch tapered Style C chrome silicon spring seats against a large diameter flat upper end specific to the full-size GM spring perch geometry. The single adjustable GS401 shock offers an 18-position valve dial that adjusts compression and rebound simultaneously. This kit installs with both factory OE stamped steel control arms and QA1 tubular control arms. Each shock is 100% dyno-tested, serialized, and serviceable by QA1 Authorized Service Centers. Register at QA1 before installation to activate the Limited Lifetime Warranty.

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