Muncie M21 or M22 ?
Thread Starter
Slingshot
Joined: Dec 2001
Posts: 3,817
Likes: 24
From: Charlotte NC
Muncie M21 or M22 ?
How do you tell the difference between a Muncie M21 and M22 transmissions? Also, are all M21 close ratio? If not, how do you tell a wide ratio from a close ratio sans pulling it apart and counting teeth?
Pro
Joined: Sep 2005
Posts: 747
Likes: 0
From: Calgary '85 Z51 coupe
M21 is the close ratio that everyone wanted; I think the M20 works better for most applications due to higher first gear.
Splines and rings changed depending on what year they were made. This site has a list of casting numbers and number of rings on the input shaft.
http://www.5speeds.com/muncie2.htm
Splines and rings changed depending on what year they were made. This site has a list of casting numbers and number of rings on the input shaft.
http://www.5speeds.com/muncie2.htm
Last edited by zoro; Feb 10, 2008 at 01:06 PM.
Thread Starter
Slingshot
Joined: Dec 2001
Posts: 3,817
Likes: 24
From: Charlotte NC
M21 is the close ratio that everyone wanted; I think the M20 works better for most applications due to higher first gear.
Splines and rings changed depending on what year they were made. This site has a list of casting numbers and number of rings on the input shaft.
http://www.5speeds.com/muncie2.htm
Splines and rings changed depending on what year they were made. This site has a list of casting numbers and number of rings on the input shaft.
http://www.5speeds.com/muncie2.htm
Instructor
Joined: Feb 2008
Posts: 158
Likes: 0
From: Houston TX
And to further elaborate, I had an M22 in a moderately "built" big-block (LS5) Chevelle SS. It laughed at all the abuse I could throw at it for years. Which makes me laugh when car manufacturers "can't" make trannies strong enough... but I digress...
Drifting
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
Yea...the Super T10 is supposed to be much stronger, but you put a Hurst shifter on a Muncie and it was sweet shifting. I could lay on my back and stick one in by myself too; (light weight).
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Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
I don't think a ST-10 is as strong as a Muncie. ST-10 hit Chevy's in late 74. Muncies survived the 60's and early 70's.
But either would grenade with some traction and even moderate HP (350-450).
But, you can purchase a new Muncie that's much stronger than the original,..about $1800. Here's the link:
www.autogear.net
Money well spent!
But either would grenade with some traction and even moderate HP (350-450).
But, you can purchase a new Muncie that's much stronger than the original,..about $1800. Here's the link:
www.autogear.net
Money well spent!
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
You can purchase a new Muncie that's muuuuch stronger than the original,..about $1800. Here's the link:
www.autogear.net
Money well spent!
www.autogear.net
Money well spent!
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
M22 will let you know. They're bulletproof/nukeproof
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
4 speed
the 4+3 is a super T-10 with an overdrive on the back. Find one of those, and modify it back to just a 4 speed.
They can handle 450 Ft. Lbs of torque, and they are close ratio, and is the latest factory ititeration of the beloved box. oh, and they go for $500-$600. and if you find one, I'll give ya $300 for a working overdrive unit, '87 and later.
ding ding ding!
They can handle 450 Ft. Lbs of torque, and they are close ratio, and is the latest factory ititeration of the beloved box. oh, and they go for $500-$600. and if you find one, I'll give ya $300 for a working overdrive unit, '87 and later.
ding ding ding!
Last edited by coupeguy2001; Feb 15, 2008 at 02:26 PM.
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
check ratio with trans removed from vehicle by LIGHTLY clamping "vise grips" to input and output shafts, select "1st" gear and count front (input) shaft rotations reqd to rotate output shaft one full revolution..."close" ratio is 2.20:1, seen as abt 2-1/4 revolutions of the input to one rev output...ONLY way to determine if it's a "rockcrusher" is to pull the side cover and observe the "angle" of the gear teeth (the 'rocky' gears have noticeably less angle)
