2008912 · C3 Tech/Performance - Gear ratio difference between M20, M21, M22 ?? - I just read a great article on the difference between wide ratio and close ratio trannys, but would like to know from those that have been dirving them a while, rather than just reading an article: --> Please confirm or correct my understanding...
view more202479 · An M-22 "Rock Crusher" is a Muncie four-speed transmission for cars made by General Motors in the 1960s. Identify a transmission type correctly before fitting it into your car. If you have the incorrect transmission, your car may not function properly. You can identify several unique signs that identify an ...
view more2008830 · The "Rock Crusher" was built for road racing, with the angle of the gears straightened out to prevent excessive wear in the front bearings due to the forward thrust component of the force vectors caused by the angle of the stock gear (angled to prevent noise and increase the contact patch of the gear for added strength). So in effect the …
view moreBy. John "Gunner" Gunnell. Transmissions are an essential part of hot rod builds. One of the most common swaps involves a Muncie 4-speed. These are easy to adapt to a wide range of hot rods. There are three basic types of Muncies: M20, M21 and M22. A Muncie differs from a Saginaw transmission in that its reverse lever is in the tail housing ...
view more200559 · I crawled under the car this morning and did see all three shifter on the side cover. This bumbed me out since I had previously read that this was an indication that it was a Saginaw not a Muncie. It does have a 7 bolt side cover. Doe this mean it's still an M22 but just manufactured at the Saginaw assembly plant or it's not an M22 "Rock Crusher …
view more20081028 · Someone correct me if I'm wrong but I think the M22 rock crusher is a close ratio trans with straight cut gears vs. normal helical cut gears?
view more2002115 · M22 is a rock crusher because of the gear noise. to reduce gear noise in a normal car, engineers put in a helical cut gear at 44 deg ( I believe). THis provides a quite comfortable ride but at the cost of strength and the additional side loading on the tranny case caused by the gear tryto get pushed into the case.
view more2017613 · The Muncie four-speed was produced in two ratios: the wide ratio (M20) and the close-ratio (M21). That being said, there was a second, close-ratio version (M22) that was developed to survive duty behind engines with a higher torque output, and was known as the “Rock Crusher.”
view more202328 · I got a stock M22 (2.20 first) replacement set (warning, they use back cut synchro teeth) along with their mainshaft and torque lock sliders (with back cut synchro teeth to match the gear set).
view more2013416 · 396 posts · Joined 2011. #8 · Apr 17, 2013. The 572 has a torque output of 685 lb ft. A Muncie M22 is only rated to 500 lb ft (matched to the output of a 454 LS6). A well built TH400 is your best option. 1955 2dr hardtop highboy, olds tripower, 4 …
view moreBased on over 30 years' experiences in design, production and service of crushing and s
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