In part two, the initial handling upgrades were an OEM strut tower brace
and a widened, lightweight wheel and tire set. These pieces greatly
improved cornering confidence, something borne out by Traqmate's GPS
telemetry. But being a track junkie, I want even more corner-gobbling
prowess from Project Z4M.

For
a good start on any suspension upgrade, it's important to set goals and
do the homework. I also recommend talking directly with experts, tuners
and race shops specializing in your particular car. As a daily
driver/track day warrior, several points were necessary to achieve my
handling goals: a slightly lower center of gravity; fully adjustable
shocks; OEM ride quality (or close to it), and more adjustability of
alignment settings to improve the tires' cornering contact patch.

Research
led to KW Suspensions' Variant 3 (V3) coilovers. In my experience, KW
coilovers stand apart in aftermarket suspensions by providing true
individual rebound and compression adjustability at a fair price. This
setup also allows a wide range of ride height adjustability and
combines high-quality German engineering with stainless steel struts,
high-tensile springs, and state-of-the-art damping technology. The Z4M
V3 kit comes with comfortable progressive-rate springs, which some
track fiends may look down their noses at. However, I'll demonstrate
that this setup completely satisfies the first three upgrade goals and
still improves lap times significantly.