Muncie 4-Speed Transmissions: How to Rebuild & Modify

Paul Cangialosi

Oct 2014 · S-A Design Book 9 · CarTech Inc

About this ebook

The Muncie 4-speeds, M20, M21, and M22 are some of the most popular manual transmissions ever made and continue to be incredibly popular. The Muncie was the top high-performance manual transmission GM offered in its muscle cars of the 60s and early 70s. It was installed in the Camaro, Chevelle, Buick GS, Pontiac GTO, Olds Cutlass, and many other classic cars. Many owners want to retain the original transmission in their classic cars to maintain its value.

Transmission expert and veteran author Paul Cangialosi has created an indispensible reference to Muncie 4-speeds that guides you through each crucial stage of the rebuild process. Comprehensive ID information is provided, so you can positively identify the cases, shafts, and related parts. It discusses available models, parts options, and gearbox cases. Most important, it shows how to completely disassemble the gearbox, identify wear and damage, select the best parts, and complete the rebuild. It also explains how to choose the ideal gear ratio for a particular application. Various high-performance and racing setups are also shown, including essential modifications, gun drilling the shafts, cutting down the gears to remove weight, and achieving race-specific clearances.

Muncie 4-speeds need rebuilding after many miles of service and extreme use. In addition, when a muscle car owner builds a high-performance engine that far exceeds stock horsepower, a stronger high-performance transmission must be built to accommodate this torque and horsepower increase. No other book goes into this much detail on the identification of the Muncie 4-speed, available parts, selection of gear ratios, and the rebuild process. 

About the author

Paul Cangialosi is owner, proprietor, and top wrench at Medatronics Corporation and 5speeds.com in Tequesta, Florida. He first started working on cars at the age of 12 and his automotive passions have burned bright ever since. He has pursued his passion for manual transmissions for nearly 30 years. Today Cangialosi's businesses offer 12 different rebuild kits and 6 new transmissions as well as rebuilding, fabricating, and design services for high-performance manual transmissions.