Hi, what you may currently notice with the standard alignment settings, is the need to constantly correct the steering when driving on a fast road, for example , a dual carriageway or motorway, at speeds in excess of 40mph. The steering will feel comparatively light and will require 100% attention, a slight error in concentration, maybe to talk to your passenger or fiddle with the audio controls, will result in unconscious movement of the steering sending the car off center.
Fast road alignment settings are designed to assist the driver in taming this unwanted character of the mx5. The small camber, toe and caster adjustments increase the weight of the steering, sometimes making you think “do i actually have power steering!”. But the constant wandering is not so evident so a good thing as it also increases driving enjoyment.
However, although all MX5s will benefit greatly, if you have a standard height mk3 mx5, the camber adjustment cannot be optimized, so the gain is less than the lowered car. Between 340mm and 350mm measuring from center of the hub and the wheel arch is the best height for the fast road settings.