Steering Modification

[Cobra #3170]

Originally Posted by strictlypersonl

100% Ackerman is nice for low-speed driving, but is not ideal for racing. True race cars actually use negative Ackerman to compensate for the higher slip angle of the outside tire. They don't care if there is tire scrub in the pits.
Article on Ackerman

That used to be more true than it is now with extremely low profile tires, I am running 18x30 tires and if you read the post this is for AUTOX which rarely exceeds 70 mph. Some formula Atlantic cars actually ran more than 100% ackermann on tight street circuits to get better turn in. Original 427 Cobras had reverse ackermann because Shelby heated the steering arms and bent them inward to clear the 7.5: mag wheels, those cars under steered like dump trucks. I corrected that situation on my Cobra in 1969 by reversing the left and right steering arms and installing a rod end in place of the large tie rod end for clearance to the brake disk and wheel. The car immediately improved with no other changes in spring or bar rates, granted a Cobra is not a true race car but we are talking Cobras here, not race cars. I once owned a parallel steer March 78B Formula Atlantic and turn in was so bad we had to add toe out to get decent turn in. The toe out made in very unstable in a straight line. Adding ackermann to that car fixed both issues. I don't doubt that ackermann isn't always the answer, it depends on so many other variables like roll stiffness, torsional stiffness, tire aspect ratio etc, etc but in the case of my Cobra it works quite well.