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3963537 - Big Block Chevy 145 (Mark IV) External Balanced 2-Piece Nodular Iron Flywheel-12-3/4" Dianeter- 15 Lbs, For 10.4" Clutch Only

This product may require vehicle validation(s) for proper fitment. Please contact us to confirm correct vehicle fitment and usage.

Availability: Item has been discontinued and is no longer available


This counterweighted flywheel is designed for externally balanced 454ci big-blocks. Its lightweight design reduces the engine's rotating mass and improves its throttle response. This flywheel uses a 10.4" diameter clutch. Its ring gear outside diameter is 12 3/4". Flywheel ID #3935411. Approximate weight 15lbs. Technical Notes: This flywheel is unbalanced; do not use with internally balanced engines. Use with counterweighted balancer P/N 3963530. 153 tooth starter ring gear. For use with Mark IV engine only.

Application List



  • 3963537
  • 3963537
  • Chevrolet Performance Parts
  • Item has been discontinued and is no longer available
  • New


Shipping Information

  • Item Requires Shipping
  • 15.0 lbs.
  • W13.9000” x H9.2000” x L14.4000”

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