2003 Nissan 350Z Tuning - Z Thrash - Tech Feature

Despite a significant increase in width, the tires were lost in the huge wheel wells. The 255/40R-17s we used on the rear actually fit on the front, and would probably do so with anything from the 38mm offset we used to at least a 32mm offset. In the rear, 275s or even 285s should fit with no problem.

Suspension
We learned early on that the 350Z would share its suspension geometry with the Nissan Skyline, a.k.a. Infiniti G35. Months before we even laid eyes on the Z, we borrowed a G35 and drove it 450 miles to Ground Control's suspension development lair outside Sacramento, Calif. With no time for trial and error, we told the engineers they had one day to build a suspension for the 350Z that would work on the first try.

They didn't even blink. Three months later, we replaced the front spring and shock with Ground Control's Advance Design coil-overs. The lightweight, aluminum bodied shock was designed and built in-house at Ground Control. Since they're used to building race suspensions, building a custom-valved shock with specially-fabricated mounting hardware is just another day at the office.

With the space constraints in the rear spring seat, there was less than two inches of adjustment in the rear spring perch. At the top of its adjustment, the car sat very low. We had been provided with a stiffer alternative rear spring, which would compress less and allow us to raise the rear, but after a quick test drive at this height, we were amazed to find the Z's suspension has so much compression travel that it actually worked.

The lower stance transformed the car visually. What once was thick and somewhat chunky was suddenly long, low and sleek. Driving through the city and up in the mountains, the car looks entirely different with it's new stance. Though the Ground Control suspension does work properly at this height, it is low enough to make speed bumps, driveways and discarded burrito wrappers into serious road hazards. If we wanted to drive this car for more than two days, we would probably raise it a hair.

At the top of each shock is a three-way adjustment for compression damping, and a continuous adjustment for rebound. Driving on the street, the shocks were perfectly matched to the provided spring rates, even with our first guess adjustments. On the slalom, however, with the opportunity to repeat the same exercise with different settings, we found increasing front compression damping to sharpen the steering and improve our times.

The adjuster for the rear shocks is inaccessible when the shocks are installed. Removing the rear shocks is fairly simple but, even with power tools, it's still a 15 minute operation at best. We stuck with our first guess adjustment throughout the test. In the future, Ground Control may invert the rear shock to place the adjuster on the bottom.

Handling with the new suspension and tires was stunning. The already impressive 70.2 mph slalom speed jumped to 71.2, and the stock 0.88g on the skidpad seemed like the work of a tricycle next to the 0.98 it could pull now.

On the road, the car felt untouchable. The steering response and massive level of grip was in another world but, strangely, the stock viscous limited-slip diff. didn't appreciate the extra grip. Even in stock form, the diff. felt weak, allowing the inside tire to spin briefly before transferring torque to the outside wheel. With the stickier tires, though, it was completely overwhelmed. Mash the throttle in a tight, second gear corner and the stock car would deliver a glory slide, but with the RA-1s, the inside tire simply spun. Aftermarket limited slips will be welcome in the new Z.

Brakes
Planning our six-hour tuner attack, we didn't even consider doing brakes. Engineering and installing a usable braking system on an entirely new car in such a short time is simply too complex.