I've recently done a bunch of research on this. The real difference is in the toe setting. With the old tires you needed toe in to compensate for the sloppiness of the tires. With radials you want 0 - 1/16" of toe in. If you leave the toe the way it was, your car will wander all over. After learning this and getting my car out on the freeway a bit more, I have found this to be true. It takes a
lot of steering (about 15 degrees) to keep it in the lane!
Unfortunately there were other differences that aren't so easy to fix. Radials transmit more road noise (don't know if my car shows that, I always have the top down! :) ), so some sort of isolators were added to the driveshaft to compensate for that. Radials are also much harsher over expansion joints (my car
definately shows that) so the suspension bushings were redesigned. My thought now is that I'm going to replace my black wall :yuck: radials with bias ply wide whites.
Most of that was from the Spring 2001 issue of Invention and Technology magazine. There is not
any hard facts on what
exactly to change when using radials. I checked with Coker (no response), Diamond Back Classics (very helpful and interested ion the issue, but didn't really know) and alignment machine manufacturers. Most will tell you there is no difference, which is just not the case.
Oh yea, I've had a wheel cover fly off too.
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