Adding shims to the front of the upper control arm will increase positive caster to answer that simply. To answer the main question. I haven't seen anyone do the Caster Mod with tubular control arms yet but I assume that it would be better simply because the arm isn't as bulky. I set my alignment up and wasn't able to get it over 3 degrees positive. I haven't done the mod yet It did feel better but it still felt dead. Doing the Caster Mod is a must if you want it to handle better.
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