The transformation of the Red Zed from a basic 2007 Nissan Nismo 350Z to proper racecar is almost complete. It has gone from road car to turning its first laps in the space of three months and, while it is not yet a racecar, it’s awfully close.
When we last left the Z it was having the cage and other safety equipment installed. That’s one of the most complex and, if you’re doing the rest of the work yourself, one of the most expensive steps in the transformation. Unless you’re an expert welder, you’ll be shelling out a bit of money for that — and, should you need that cage, it will be money well spent.
Blackbird Fabworx crafted and installed the $3,500 cage, which easily passed tech inspection. During inspection, the quality of the welds, construction and installation were noted. Although new to building a Spec Z cage, Blackbird Fabworx is no stranger to building cages for NASA racers, and as you can see in the photos, the workmanship is first rate.
For example, the driver seat mounting hardware consists of top quality fasteners, blue coated 12.9 metric where applicable and high-quality, all-metal lock nuts with Loctite on the threads. Further, built-in loops for the window net on the driver’s door bar prevent any unwanted shifting.
Fortunately, the rest of the conversion process, while not exactly a walk in the park, is fairly straightforward.
“For the spec suspension install, you take the lower shock mount out and then the front shock tower unbolts and it pulls out,” says Jeremy Croiset, builder and driver of the Red Zed. “Then you install the whole new unit, which is nicely designed by KW Suspension and includes the top hat and everything. You need nothing from the original factory stuff. It’s a simple swap.”
The rear is slightly more complicated than the simple McPherson strut exchange at the front. You unbolt the spring holder from the bottom, and then pull out the shock after undoing the top and bottom mounts. When you disconnect the shock, the arm will drop down and the spring can be changed, Croiset explains.
The rules allow for substitution of the stock differential, whichever stock unit it comes with, for the Autotech Driveline Wavetrac torque-biasing differential, which Croiset chose to use. That takes care of most of the spec stuff. But even in spec classes, there are some freedoms. For brake pads, Croiset chose Hawk DTC-70s at the front and DTC-60s at the rear.
“That was just a starting point,” he says. “We have some different compounds to try. But that setup works great. The DTC is the newest compound and the DTC-70 is developed for a heavier road-racing car. I went with the 60 on the rear because I didn’t want to have as much lockup characteristic.”
Along with that, Croiset bled the brakes and swapped other fluids as well.
“We went with Motul 600 for the brake system,” he says. “We also put Motul 600 in the clutch system because the fluid tends to overheat if you don’t. We put some heat shielding around the clutch line that runs in between the transmission and the master cylinder for the clutch, because that line runs right next to the header and that can overheat and boil the fluid, and then you lose your clutch pedal.”
Croiset put Enkei GTC01 wheels on the car, 18×9 all around. Although the rules allow for a 10-inch-wide wheel at the rear, using the same size at both ends allows for easier tire swaps.
With that, the Z was ready to hit the track, except for a missing part of the fire system. That small problem kept Croiset from entering the late-June race at Buttonwillow Raceway Park as he had planned. Fortunately, he didn’t need the fire system to get some track time in the HPDE group, so the weekend wasn’t a complete loss. He now has a feel for the car, a baseline for the setup and a pretty good idea of what it will do, and what it needs next.
“My first impressions are that it’s a very well balanced car with tons of grip,” he says. “It’s pretty easy to drive, a fairly forgiving car. Ultimately it’s a very fun car to drive. It has a ton of grip and enough power that you can go pretty darn fast. You can get yourself into trouble, but because it’s got enough grip, it’s not on the knife edge all the time and you can get on the power fairly early and not worry about the rear end walking away from you.
“It still requires enough skill to drive at the limit that everybody shouldn’t be fast in the car from the get-go,” he adds. “It does require some skill to go fast in it.”
Croiset, who was largely responsible for writing the Spec Z rules, had a pretty good idea what to expect from the car. Still, there were some revelations.
“How flat the power band was, that surprised me,” he says. “But I’m coming from a Honda with a VTEC engine, so everything seems flat in comparison. Another thing that surprised me is how good the car is on track with such little changes. If you think about it, the car has a differential, a different suspension, wheels, tires and brakes, and that’s it. And the car is just phenomenally fun to drive.”
The Z was turning 2:07 times around Buttonwillow’s counter-clockwise No. 1 configuration. Croiset estimates that it’s quite capable of getting into the 2:06 range, which compares favorably with the 2:11 and 2:12 lap times of the Spec Miatas that same weekend.
Some of the time, Croiset thinks will come from having the proper sway bars in the car. We’ll cover the installation of those in a later issue of Speed News. The rest will be earned with a few other tricks that he thinks will improve the Z.
“I’m going to install some test pipes from a company called Berk Technology. It makes a direct replacement for the stock cats, with an O2 sensor and everything. You’ll experience a horsepower increase and you never have to worry about the stock catalytic converters clogging up on you,” he says. In addition, he’s also considering a more-free-flowing intake air filter and may elect to send the ECU out for a reflash, but that last item is secondary to getting the car on track and working correctly.
By the time you read this, the Red Zed should have made its debut in a proper race. Look for the final installment of the build to cover its first laps in anger.
