I have a 71 Dodge Demon that has a slant six 225 with a three speed on the floor transmission. I have converted the car to BBP front disc brakes and changed out the 7 1/4 to an 8 3/4 3.55 posi with 10 x 2.5 BBP rear brakes. My question is now I want to convert to a 4 speed but have found a cast iron 3 speed with overdrive transmission. What else do I need? Can I use a regular 4 speed shifter? Hopefully someone has already done this conversion and can help with a parts list.
Chrysler Corp. did, and.....
You cannot use the 3 spd bell, the input shaft uses a large brg./retainer & the trans pattern is different. One could machine the retainer reciever bore in the bell oversize, but attn needs to be paid to release-arm fulcrum mounting bolt location, & there are at least 2 diff fulcrums moving the position in relation to the mt bolts. The 3-4 shift lever is mounted "upside down" to change the direction of shifter motion from backward to forward to put 1:1 in "3rd" position, this requires a special 3-4 shift rod, depending on the stock rod You can "make do". Yes You can use a std 4 spd shifter...
There are some 3/4 speed bells with both patterns I believe, but I couldn't tell on what & when they were used, best of luck on the swap...
