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Skunk2 521-99-1000 Coilover Race Spring 10kg/mm 6" Elliptical

Manufacturer

Picture for manufacturer Skunk2

Part Number

521-99-1000
6 reviews
Sale Price

$95.66

Estimated ship date Friday, November 20

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Product Details

The Skunk2 521-99-1000 is a 6-inch elliptical coilover race spring rated at 10 kg/mm (559 lb/in), engineered as a direct replacement or upgrade spring for Skunk2 Pro-ST, Pro-C, and Pro-S II coilover systems. Sold individually, this spring allows experienced tuners to dial in a custom suspension setup tailored to their specific performance goals — whether for street, track, or competition use.

Designed to install approximately one inch lower than standard Pro-C / Pro-S II coilover springs, the 521-99-1000 gives tuners precise control over ride height and handling balance without sacrificing spring quality.

Key Features:

  • Spring Rate: 10 kg/mm (559 lb/in)
  • Length: 6.00 inches
  • Inner Diameter: 2.50 inches
  • Profile: Elliptical (tapered) design
  • Material: CNC-wound SAE 9254V high-quality spring steel
  • Manufacturing: Shot-peen stress relieved for increased fatigue life
  • Finish: Powder coated with specialized phosphate treating for corrosion protection
  • Sold as: Single spring (one per part number)

How to Read Skunk2 Spring Part Numbers:

Skunk2 race spring part numbers encode key specifications. Example: 0600.250.010

  • 0600 — Spring length (6.00 inches)
  • 250 — Inner diameter (2.50 inches)
  • 010 — Spring rate (10 kg/mm)

Spring Rate Conversion: 1 kg/mm = 55.88 lb/in

Compatible with Skunk2 Pro-ST, Pro-C, and Pro-S II coilover kits. These are the same high-quality springs included standard in Skunk2 adjustable coilover assemblies, now available separately for custom tuning configurations.

Products specifications

ID

2.5"

Length

6"

Rate

10kg/mm

Style

Straight

Ordered a sling to store my roof rack. There was an issue with the supplier which was quickly resolved by the Autoplicity staff. Great customer service -- most responsive I've ever seen.<br><br>Best prices around.

Super easy to browse web site and find the product I wanted.<br>The price was unmatched.<br>Shipping was fast and cheap.<br>Super shopping experience.

quick great value

Great prices, helpful customer service. Ordered 2 by mistake. And they got it cleared up real fast. Saved over $80 off retail. Will be ordering from the, again!!!!! <br>

Rather amazing and uneventful service in this day and age. Ordered a Thule bike rack for my Nissan Murano. It was in stock (unusual for high-end specialty products), shipped the next day, and was on my doorstep in a few days (excellent for a 60 lb. large box). I'd buy anything from these people without any reservation. AND, your order is insured - completely superfluous. Oh, and did I mention, the lowest price I could find ANYWHERE, and not by a few dollars - a lot.

Excellent service with the actual stock on hand, shipment was made the next day and a tracking number was provided. I have tried 2 other online supply stores which don't know what they have in stock.

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