The Throttle Valve Cable or “TV-Cable”, as it is commonly referred to, is a cable that connects your engine to your transmission in order to tell it when to shift. The 700R4/2004R TV Cable can be very tricky to get right.
If you are looking to buy a 700R4 TV cable, there were tons of different sizes of cable available for each make and model of car, we recommend going with a universal cable like the one from TCI below.
How does a TV cable work?
The TV cable connects to the throttle body or carburetor with a similar method as the one used by the TH350 and the TH400. The difference is that the TV cable works a lot more like the throttle position sensor on a later model transmission, while still maintaining a physical connection between the engine and transmission. This allows the TH700R4 to shift more smoothly than it’s predecessors, while at the same time not entering the world of shift tables and electronic controls.
What the 700R4 TV cable do?
The 700R4 TV cable does a lot more than downshift like the old TH350 kick-down cable would. It controls the transmission in a much more sophisticated way.
The TV Cable also controls these functions:
- Controls shift points
- Controls line pressure
- Detent Downshifts
- Part Throttle Downshifts
Getting the TV Cable to Work With a Carburetor
When swapping a 700R4 into a car that was previously equipped with a TH350, TH400, Powerglide, etc… there are two things that you’re going to end up having to do. The first is you’re more than likely going to have to adjust the driveshaft length.
The second thing that you’re going to have to do is dial the TV cable into the new car. This means installing it with the proper bracket in order to get the geometry right. There are two distinct types of brackets that you may need in order to get the TV cable dialed in to it’s new home. They are lined out below.
Adjusting the TV Cable
The TV cable is pretty easy to adjust, but difficult to calibrate if that makes sense. There’s a lot to it, and here’s a terrific write up from Summit. If you are a visual person, here’s a YouTube video of someone going about the steps to adjust the TV Cable:
Make sure that you have the right tv cable. There are tons of different versions of the TV cable, so make sure that you have the one that was meant to go in your car. Don’t re use one. They stretch and go bad like anything else. If you don’t know what TV cable to get, just go with a universal cable.