Does any one know the difference between a muncie 4 speed trans and a powerglide. Have a 62 impala SS with a 409 and a turbo 400 trans on it. Like to get the original tans. and shifter for it. Not sure what came with the car. If any one has any info. Like to know
Well for starters the Muncie four speed is a manual transmission you have to shift it your self. OK (thanks for the straight line) I believe you are interested to know about swapping a Muncie or four speed in place of the TH400. The Muncie is a full conversion from automatic to standard (clutch pedals, clutch hardware such as cross shift, two clutch mounting balls springs and rods. a new bell housing a new flywheel (11" 168 tooth) a new drive shaft as yours will be too short since the Th400 is longer than a Muncie) new front yoke because the Th400 is bigger and stronger than the Muncie, new cross-member (the TH400 has it's own cross-member), a hole cut in your floor boards after which you weld in the four speed hump, a new Hurst Shifter (good luck in trying to get a period correct Muncie shifter), shifter boot, new rug for your new floor hump unless adding a console to cover the big hole in the carpet (may or may not cover it), pressure plate and clutch disc, new throw out bearing, and install a fresh bearing in the back of the crank for a pilot bearing, a Muncie four speed (getting near the price of another project car), throw out fork and return spring and a throw out fork ball. May have forgotten something but that should about cover it.
The Muncie four speed is the exact same length and uses the same cross-member and drive shaft as the PowerGlide, which back in 1962 was made of cast iron and didn't hold much in terms of power. All of the parts inside a period correct cast iron PowerGlide can be upgraded to handle a 409 horse 409 or a even a 425 horse 409.
Personally I would keep the TH400 it is stronger than the Muncie and the PowerGlide and is already working. If not it is cheap to rebuild. By the way if you are looking for a period correct tranny the Muncie was not introduced until 1963 to replace all of the Borg-Warner T-10 transmissions that broke behind a 409 under warranty (they replaced the rear end in 1964 with a 12 bolt because the 409 started busting them once the Borg-Warner was replaced).