Solving the Excess Ackermann Problem If your car gains or loses toe, there are a couple of ways to correct the situation. You can adjust the length of one or both of your steering arms to compensate for Ackermann effect. This works best for a car where the steering wheel is always turned to the left as opposed to a dirt car that sometimes has the wheels turned to the right. Lengthening the left steering arm will reduce the amount that wheel turns with a measured steering input, which reduces Ackermann effect. The opposite is true for the right steering arm-we would need to shorten it in order to reduce Ackermann. We can also change our drag link to move the inner ends of the tire rods forward to reduce Ackermann or rearward to increase it or to reduce reverse Ackermann effect.
If your spindles were not designed for your steering system, change to the correct spindle design and possibly have some lightweight ones fabricated to the exact specifications as the correct ones. I did that way back in 1997 with a brand-new car.
Our old car, which won a Regional NASCAR championship, had the old cast spindles and the new one had the rack light spindles. The new car did not turn well. We replaced the light spindles with the old-style cast spindles and the problem went away. We then asked the car builder to fabricate new ones to the same dimensions as the old style cast ones.
He asked, "Why?" We said never mind, we were paying him, just do it. A few weeks later, a new car arrived at one of the same car builder's dealers in Nashville with spindles identical to the ones we had fabricated. Coincidentally, I was there to help with a seminar and recognized the copy.
For a rack-and-pinion steering system, moving the rack forward in relation to the outer tie-rod ends will reduce Ackermann. Most Dirt Late Model cars use the rack systems. So, we don't have the convenience of only having to improve our Ackermann effect in one direction, it must be correct for left or right turning of the wheels.
Asphalt Late Model cars are also designed with rack systems. Instead of changing the length of the steering arms, it might be best to move the rack and keep equal length steering arms when working to reduce excess Ackermann.
A Caution Do not make spindle changes without knowing how the change will affect your moment center location. You may be making a positive change in your steering system and a negative change in the moment center design. This problem relates to spindle height differences where the upper and/or lower ball joints will change height with a spindle change. This changes the upper and/or lower arm angles and along with that the moment center location.
Make sure you know how much each of your tires are steering and reduce the Ackermann effect if needed. Then, when you balance your setup, both front tires will be working in perfect alignment to steer your car. A good steering race car is one that will have more turning power and is therefore more capable of running up front and winning races.
The chart shows how much difference in turning distance at 10 feet relates to toe. For an
In a Dirt Late Model or an Asphalt Late Model with rack-and-pinion steering, moving the ra
This spindle has a slotted hole where the tie-rod end mounts to the steering arm. This all