Home Page › Forums › Discussion Topics – Ask the Experts › 4 speed automatic transmissions › Reply To: Re: 4 speed automatic transmissions

That trans has 3 distinct gear ratio, and a variable ratio fluid coupling that
sometimes is referred to as a 4th speed (not by me). I don’t believe there
is another automatic that just bolts up. The Special 215 used a torque
converter and 2 speed. I collected that flex plate & flywheel in hopes of
bolting on a newer torque converter trans, like a TH350 with an adapter
plate. But never finished the idea.
That trans doesn’t like abuse, and are hard to get fixed. In a Jetfire that
trans is totally unable to handle the torque, I could never shift under
power. In addition, the shift control mechanism is badly suited to a hot,
small displacement engine. My opinion is, all Jetfires should have 4 speed
manuals, or a modified TH350/TH400 trans. At one time I had 13 slim
jims around in various states of broken. good luck, Bruce Roe