QA1 27A683-6M 27 Series Monotube Shock Large Steel T-Bar/Poly 3-6M IMCA Sealed

The QA1 27A683-6M is a stock mount monotube shock absorber from QA1's 27A Series — the IMCA-legal, sealed hyperscrew variant of the popular 27 Series. Designed specifically for circle track racing applications including street stocks, hobby stocks, and mini stocks, this shock delivers consistent, repeatable performance on both dirt and asphalt surfaces.

Key Features:

• Monotube steel body construction with zinc plating for superior corrosion resistance
• 46mm hard-anodized piston for maximum car control at all shaft velocities
• Sealed hyperscrew (27A Series) — IMCA and Southern Sport Mod legal
• Compressed height: 13.35" | Extended height: 22.55"
• T-bar top mount / polyurethane bushing bottom mount
• Valving: 3 compression / 6 rebound (3-6M) — linear valving profile
• Linear valving provides a stable, predictable handling platform and improved driver feel
• 100% dyno tested and serialized for quality assurance
• Racer rebuildable and revalveable for long-term serviceability
• Made in the USA at QA1's Lakeville, MN facility

The 27A Series sealed hyperscrew design means the nitrogen gas pressure is only adjustable by QA1 or QA1 Authorized Rebuilders, keeping the shock compliant with sanctioning body rules such as IMCA. The linear damping curve allows complete control of the suspension at low shaft speeds without generating extreme forces at high shaft velocities — a setup favored for stock mount classes where consistency and driver confidence are essential.