The Ford Barn - View Single Post - Fordomatic late shifting ('57 thunderbird)

Gene F · 10-22-2020, 07:05 PM

I have a 57 Skyliner with a 292 that was a 2-brl. I changed it over to a tri-power. Turns out it was not a big deal until I decided I wanted to keep my automatic trans. After reading everything, and my own experience, I believe that the TV rod is where the trouble lies. The trans thinks that the throttle is down. That is why it's shifting late, and the pressure is higher than desired.

That TV linkage is the equivelant of a throttle position sensor on a new car. Shorten the throw of that TV linkage FROM THE MANIFOLD ALL THE WAY DOWN TO THE TRANS ARM NEAR THE PAN, and the car shifts sooner and softer. Hence longer means harder. In my case going from the Ford manifold to the Offy manifold the mounting height above the garage floor for the was lower. I had to cut my rod, and thread it more, because it was simply too long (the lower rod with the pin through it).

I have an idea. Find another car like yours, and get under it and measure how far that TV rod is above the garage floor. Then have someone reach in and hold the accelerator fully open, and measure again. There is your answer.

Just my 2-cents...

10-22-2020, 07:05 PM	#32
Gene F Senior Member Join Date: Mar 2012 Location: Ohio Posts: 1,973	Re: Fordomatic late shifting ('57 thunderbird) I have a 57 Skyliner with a 292 that was a 2-brl. I changed it over to a tri-power. Turns out it was not a big deal until I decided I wanted to keep my automatic trans. After reading everything, and my own experience, I believe that the TV rod is where the trouble lies. The trans thinks that the throttle is down. That is why it's shifting late, and the pressure is higher than desired. That TV linkage is the equivelant of a throttle position sensor on a new car. Shorten the throw of that TV linkage FROM THE MANIFOLD ALL THE WAY DOWN TO THE TRANS ARM NEAR THE PAN, and the car shifts sooner and softer. Hence longer means harder. In my case going from the Ford manifold to the Offy manifold the mounting height above the garage floor for the was lower. I had to cut my rod, and thread it more, because it was simply too long (the lower rod with the pin through it). I have an idea. Find another car like yours, and get under it and measure how far that TV rod is above the garage floor. Then have someone reach in and hold the accelerator fully open, and measure again. There is your answer. Just my 2-cents...