muncie id

i pulled the trans out of the 68 parts car and i cant find any positive info. it is the #'s matching trans. from the car. the input shaft has 1 groove. the date code is P8O24E. the "P" is muncie, the "8" is 1968, the "O"??? (supposed to be the month), the "24" is the day and the "E"??? (supposed to be the gear ratio but they only go A,B,C)

 

As far as I know, the only Muncie with a 1 groove input shaft is an M21. Is it course input or fine spline?

 

I believe the O is Oshua plant and thus the E is the month. the ratio letter designation didn't start until 1969.

 

i was thinking m21 but wasnt sure, theres so much diffent info. its a course spline.

 

that could explain it. some say the ratio designation started in 68 so i wasnt sure. thanks for the info.

 

how would the M21 work with a 3.08 rearend?

 

awesome! that's the combo buick put in the 71 GS 350 with a 4 speed!

 

I would say that rear gear is a bit too tall for an M21. They have a 2.20 first gear. I have an m20 in my car which has a 2.52 first gear and I have 3.23s in the back, and I wish I sometime didnt have to skip the clutch as much. Not saying its real bad, but that combo will be worse.