oletrucks
[Top] [All Lists]

RE: [oletrucks] Muncie Trannys

To: Gary Stutz <gary@mx.serv.net>, oletrucks@autox.team.net
Subject: RE: [oletrucks] Muncie Trannys
From: MIKE RAHL <MRAHL@martinmartin.com>
Date: Sun, 25 Jul 1999 13:43:01 -0600
Gary,

I had photocopied the following info from a source which now escapes me:

The Muncies produced from 63-65 had 7/8" countershaft, brass configuration
synchronizer rings sans shoulders.  Two different gear ratios.  Close-ratio
(2.20:1, 4.64:1, 1.28:1, 1.00:1), wide-ratio (2.56:1, 1.91:1, 1.48:1,
1.00:1).

In 1966, a revisions included 1" countershaft and a combination of wider
brass synchro hubs and wider synchronizer rings.  Close-ratio stayed the
same, but wide-ratio changed (2.52:1, 1.88:1, 1.46:1, and 1.00:1).

M-22 "rock-crusher" produced from 65-74 had 9310 nickle alloy gears with a
low helical cut of 21 degrees, which produced considerable noise.  1"
countershaft, input shaft was either a 26-spline or a conventional 10-spline
unit.  Gear selection limited to 2.20:1 close-ratio setup.

"Third design" or "heavy duty" gearbox debuted in 1971.  Not as strong as
"rock crusher" but beefier than past conventional transmissions.  32-spline
output shaft (as opposed to the previous 27), input shaft was standardized
at 26 splines.  Gear ratios identical to the 1966 and newer transmissions.

Long-tailshaft model produced from 64-68 carried all of the features of the
previously described versions (per the specific model years), but featured a
six-inch longer overall length for use in full size Pontiac and Oldsmobile
passenger cars.

When we were in hich school my brother had a 68 Chevelle SS 396 (375 HP)
with a "rock-crusher".  He still kicks himself for getting rid of that car.

Mike

> -----Original Message-----
> From: Gary Stutz [mailto:gary@mx.serv.net]
> Sent: Saturday, July 24, 1999 10:30 AM
> To: oletrucks@autox.team.net
> Subject: [oletrucks] Muncie Trannys
> 
> 
> Hey Guys-
> 
> I'm getting ready to put a 300 HP crate small block in my 56 1/2 ton
> panel truck. Does anyone know what the gear ratios are on the Muncie
> four speed? I've thought about a Saginaw, because the shifter 
> kits from
> Patricks work well, but I'm not sure if the Saginaw can handle the
> torque of the new engine. I've seen references to to a 'rock crusher' 
> four speed in the hot rod world. Are these trannys Muncies? 
> 
> TIA for the experience and time of the group.
> 
> Gary Stutz
> oletrucks is devoted to Chevy and GM trucks built between 
> 1941 and 1959
> 
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959

<Prev in Thread] Current Thread [Next in Thread>