What Is Steering Ackermann? What Does It Do

What is a steering "Ackermann" and how is it adjusted differently in street cars vs. drift cars? Here, in episode 46 of Lincoln Tech "Tech Tips", Tony Angelo discusses Ackerman. The Ackermann geometric linkage design affects a vehicle's front steering capacity by determining how the front tires navigate differently going into, and coming out of, turns. In this episode of Lincoln Tech Tips, Tony describes how automotive engineers consider elements like wheel size, tire slip, and track, when determining the amount of Ackermann to build into a car.

Video Transcript:

0:00: [Music]

0:02: Welcome back to another Lincoln Tech tech-tip today. We're going to talk about Ackerman. If you're serious about your car's handling, you're probably already familiar with camber, caster, and toe. These are easy to understand parameters between drift cars and road racing because camber, caster, and toe are very much the same, but where they differ greatly is Ackerman.

0:19: Ackerman is a device designed into the front steering of your car that allows the front tires to ride on two different radii when going through a turn. By toeing out the inner wheel the more the wheels are turned.

00:29: Engineers take into account track wheelbase tire slip and other factors when they design a good amount of Ackerman in the streetcars. There are two major reasons why conventional Ackerman is not great for drift cars. First, in a drift car the wheels are turned in the opposite direction.

00:43: When you're on the turn as in the wheel to turn to the right when you're going around a left-hand turn; secondly, the wheels are turning at such an extreme angle that the Ackerman becomes exaggerated meaning that the front wheels are pointed in very different directions and that causes a ton of front-end drag at high speed and high angle.

01:01: Some pro drift cars run very mild or even zero Ackerman, so they don't have that issue with that front end drag so a car like the fishtail CUDA that's going to be primarily a street car. But we do want it to perform well on a drift track.

01:12: We're going to dial in a mild amount of Ackerman functionally where the pickup point for the steering arm is in relationship to the pivot for the spindle. It's going to control how much Ackerman your car has. If the pickup point for the steering arm is directly in line with the pivot for the spindle, there will be no Ackerman or parallel steering. And as this pickup point for the steering arm moves inward on a radius that will generate more Ackerman.

01:33: Okay, that's it for another Lincoln tech tip, let's get back to the shop.

01:38: Lincoln Tech can teach you how to have a career working with cars.

Introduction by Robert Lanni. Video by Hot Rod Garage & Lincoln Tech.