‘Syracuse’ M23: The Champion, Reimagined

The Muncie M23 is the strongest, fastest-shifting synchronized 4-speed on the market — purpose-built for musclecars, hot rods, and custom performance applications.

Whether you’re building a street legend or a track machine, the M23 delivers unmatched durability and shift feel — all in the classic Muncie footprint.

Why Choose the M23?

  • ✅ Smooth shifting, optimized RPM drop
  • ✅ Supercase standard with SAE 9310-equivalent countershaft
  • ✅ Stronger gear geometry + polished contact surfaces
  • ✅ SCCA-approved options available
  • ✅ AutoGear “controlled-clearance” synchronizers for fast, durable shifts

Gear Ratio Packages

Model 1st Gear 2nd Gear 3rd Gear 4th Gear Best For
M23X 2.20 1.64 1.27 1.00 Road course & high-rev builds
M23W 2.56 1.75 1.36 1.00 Street/track blend
M23Z 2.98 2.04 1.46 1.00 Drag & street torque builds

Additional ratio codes available (314, 324, 334, etc.) — Contact us to find your match.

What You Get

  • ‘Muncie’ install footprint — reuse clutch, shifter, driveshaft
  • Masiero Italian gears — rarely equaled, never bested
  • N-Series Supercase + mainshaft = rugged and vibration-resistant
  • Controlled-clearance synchros + Kyowa rings = built for fast shifts under pressure
  • Oil-sealed, torsion-cushioned 26-spline inputs for torque shock protection
  • Cast and machined in the USA with aircraft-grade aluminum

Resources

View documents and resources related to this gearbox in the resource center.

View Resources

Muncie Gearbox Comparison

Model Strength Shift Feel Best For Details
Muncie M20 Smoothest Easiest to drive Street cruising & lighter loads Wide ratio, ideal for new drivers
Muncie M22 Strong & mechanical “Syracuse whine” Musclecars & resto builds Straight-cut Rock Crusher heritage
Muncie M23 Fast & modern Quickest shifts Track & street & torque builds Modern materials in classic case

Not Sure Which Ratio Is Right?

Submit an EZ-Spec and our team will reply with a personalized recommendation.

Our mission? To be the best today — and better tomorrow.

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