Because we must understand how certain parts work to make the best choices for our specific application, this edition of Carl’s Tech Talk video series from Summit Racing begins with tech expert Carl Pritts explaining the finer points of torque converter operation.
The rpm at which vehicles begin to move can be changed by modifying different attributes of your torque converter, including:
- Body diameter
- Internal fin count
- Fin angle
This is where “stall” comes into play, Pritts said, before defining stall as when the pump speed and turbine speed are the same. Understanding the difference between a high-stall converter and a low-stall converter will help you select a torque converter that will work best for your vehicle.
(Learn much more about stall from our four-part series All About Stall)
Questions You’ll Need to Answer
- What transmission do I have?
- What is my flexplate’s bolt pattern?
- How many splines are on the input shaft?
- Is it a lockup-style transmission and converter?
- What is my vehicle weight?
- What is my tire size?
- What is the axle gear ratio?
Your converter should stall approximately 500-800 rpm after your engine begins to make power, Pritts said.
And then he explains why, and shows you where to find the information you’ll need to to choose a great torque converter. See for yourself.