Test fit Vision 18" wheel today
The steering stops are on the lower ball joint, they contact the LCA at full lock.
As for how much it would take, it depends on how much interference you have. It wouldn't take much, the steering stop is rotating around an axis, so, what you're modifying works in degrees. Even a small increase in the steering stop length could limit the turning radius by a couple of degrees, which would change the clearance quite a bit. That's why found it interesting that the stops weren't very precise when I compared a bunch of old ball joints- even a 1/16" change at the stop would be significant, and there was that much variation between different ball joints.
It would change the turning radius of course, but, because these stops weren't very precise it's hard to tell how much your car would change compared to say, the factory spec. Your car could already have a tighter turning radius than what the spec was if the stop is a little undersize. How much the turning radius changes would depend on how much you add to the steering stop.
I went and looked at this after I installed the 275/35/18's on my car. I had been using a lot of info from 72BBswinger, and my wheel specs were pretty much identical to his. But on his car he had plenty of room to the frame, while on mine I had contact at lock. Again, not a lot, the tires just barely touch the frame at full lock. After looking into the steering stops, I realized that there was more than enough variation in the steering stops to account for all of the difference. His car cleared because his wheels didn't turn as far, even 1* is significant.
I would use a wheel spacer if I had any extra room between the tire and the fender before I modified the steering stops, just because you are changing the turning radius of the car. Bill Reilly probably has a bit of a biased opinion, since his RMS Alterkation suspension does increase the turning radius of these cars noticeably. I personally think that's a negative, a better turning radius is a good thing. And with a factory turn radius of 37.8' it's not like these things have a super tight turn radius. Better than say, a 1971 Mustang which had a 39.8" turning radius, but that's not saying much.
The steering stops are on the lower ball joint, they contact the LCA at full lock.
As for how much it would take, it depends on how much interference you have. It wouldn't take much, the steering stop is rotating around an axis, so, what you're modifying works in degrees. Even a small increase in the steering stop length could limit the turning radius by a couple of degrees, which would change the clearance quite a bit. That's why found it interesting that the stops weren't very precise when I compared a bunch of old ball joints- even a 1/16" change at the stop would be significant, and there was that much variation between different ball joints.
It would change the turning radius of course, but, because these stops weren't very precise it's hard to tell how much your car would change compared to say, the factory spec. Your car could already have a tighter turning radius than what the spec was if the stop is a little undersize. How much the turning radius changes would depend on how much you add to the steering stop.
I went and looked at this after I installed the 275/35/18's on my car. I had been using a lot of info from 72BBswinger, and my wheel specs were pretty much identical to his. But on his car he had plenty of room to the frame, while on mine I had contact at lock. Again, not a lot, the tires just barely touch the frame at full lock. After looking into the steering stops, I realized that there was more than enough variation in the steering stops to account for all of the difference. His car cleared because his wheels didn't turn as far, even 1* is significant.
I would use a wheel spacer if I had any extra room between the tire and the fender before I modified the steering stops, just because you are changing the turning radius of the car. Bill Reilly probably has a bit of a biased opinion, since his RMS Alterkation suspension does increase the turning radius of these cars noticeably. I personally think that's a negative, a better turning radius is a good thing. And with a factory turn radius of 37.8' it's not like these things have a super tight turn radius. Better than say, a 1971 Mustang which had a 39.8" turning radius, but that's not saying much.
