Product Details

Swift Springs Bulletproof Series Conventional Springs in 5" OD and 20" length are purpose-built for the most demanding circle track racing applications where springs face extreme repeated loading. These 5" OD Swift Bulletproof race springs are manufactured in Japan from proprietary H5S.TW high-tensile alloy steel with enhanced durability, providing consistent rate behavior through loading conditions that would cause conventional springs to fail.

The Bulletproof Series was developed after years of research with top circle track racers, specifically engineered to meet the unique demands of American oval track racing at extended free lengths. All Swift Springs Bulletproof conventional springs use H5S.TW alloy for extreme fatigue resistance.

Why Racers Choose Swift Springs Bulletproof Series

  • Purpose-built for high-stress circle track and oval racing applications
  • H5S.TW alloy delivers extreme fatigue resistance and rate consistency
  • 20" free length for maximum stroke in long-travel setups
  • Engineered to survive repeated high-load cycles without rate degradation
  • Precision grinding for even perch seating
  • Developed from years of research with top circle track racers

Note: Swift Conventional Race Springs are sold individually. Select your desired spring rate from the options above.

Specifications
PART # SPRING RATE USABLE STROKE MAX STROKE MAX LOAD
lbs/inch inch inch lbs
200-500-080 BP 80 15.8 15.8 1,263
200-500-100 BP 100 15.4 15.4 1,543

Customer Reviews

See what customers think of this product.

4.6
Rated 4.6 out of 5 stars
Based on 8 reviews
100%would recommend these products
8 reviews
  • DS
    Dan S.
    Verified Buyer
    Reviewing
    Swift Springs Metric Coilover Springs - ID: 60mm / Length: 8"
    Rated 5 out of 5 stars
    Great springs

    Swift makes great springs. I haven't put these in yet, running different springs now.

    It's a matter of trial and error to get the car balanced.

    The picture is what is in the car now. The helpers are too soft so I bought assist springs as well.

  • G
    Gabby
    Flag of United States
    Verified Buyer
    Reviewing
    Swift Springs Metric Coilover Springs - ID: 65mm / Length: 4"
    Rated 5 out of 5 stars
    Always a customer

    This is my second set of springs from you guys. My car rides exactly how I want it to and lets me get the ride bight I’ve been trying to achieve. I’ll be a customer for as long as I’m modifying cars!

    S Profile picture for Springrates
    Springrates
    3 years ago

    Thanks so much, Gabby! We're thrilled you love them. You can't go wrong with Swift Springs!

  • AS
    Andrew S.
    Flag of United States
    Verified Buyer
    Reviewing
    Swift Springs Coilover Helper Springs (Flat Wire) - ID: 70mm (2.75")
    Rated 4 out of 5 stars
    Good but just one thing

    Very happy with my purchase of the BC racing BR coilovers. They compliment my car and driving style.

  • IM
    Ian M.
    Flag of United States
    Verified Buyer
    Reviewing
    Swift Springs Metric Coilover Springs - ID: 70mm / Length: 6"
    Rated 5 out of 5 stars
    Swift with springs

    Excellent customer service and product. Highly recommend purchasing from this company. Just had my first autocross with the new springs and they performed excellently. Quite happy.

    S Profile picture for Springrates
    Springrates
    3 years ago

    Thanks so much, Ian! Send us some photos of your racing too!

  • T
    Timothy
    Flag of United States
    Verified Buyer
    Reviewing
    Swift Springs Metric Coilover Springs - ID: 70mm / Length: 6"
    Rated 5 out of 5 stars
    As what I expected!!

    Great springs for the price! Made the car feel much more in tuned with the road!

Questions & Answers

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