Steven's '91 300ZX: An Old Lover Grows Up
A few decades spent drag racing and Steven wanted something else. He’d been through a few motors and a few 300ZX chassis—one combo making more than 1,000 horsepower—and he felt he needed a new way to expend his boundless energy. After some of the local Z enthusiasts lured him into tracking Thunderhill, Steven found that outlet.
It may have done more harm than help to have had a 3.2-liter JUN stroker motor powering this ‘91 300ZX Twin Turbo at that stage, but he still managed not to crash during his first few eye-opening lapping days. That was his greatest accomplishment those first days out, as he wasn’t quite quick enough to keep the well-driven Miatas at bay. Then and there, Steven accepted that seat time, a predictable chassis, and a little more grip were what made the difference here.
Fortunately, his tire needs were addressed by a shop next door which supported Ferrari Challenge cars. With all the scrub tires available to him for nothing, he started mounting them to a set of 19” 370Z wheels with the OEM Akebono brakes underneath. It wasn’t much, but it was a start.
Steven then selected a set of Powertrix coilovers and polyurethane bushings in cheap adjustable arms. Nothing exceptional, but it was sufficient for his needs at the time. He realized that seat time was what would make the biggest difference at that stage.
After a year spent running fifteen track weekends annually helped him get up to speed quickly. Furthermore, he was typically running double sessions those weekends. It didn’t take too long before he felt capable enough to assess some of the limitations of his then-current hardware. For this phase of his car’s development, Steven consulted with Andre Haranto to ensure every additional upgrade brought with it significant gains.
Around that time, it was evident that the JUN motor was a little tired. One year of regular road racing and three years of quarter-mile blasts before that had cracked the crankshaft and Steven had been noticing the oil pressure dropping. Out went that motor and in went another which had been sitting on a shelf for a few years.
This 3.0-liter motor sports a Callies crank, Crower rods, CP pistons, JW RMS cams and Tomei solid lifters, a pair of GTX2860 turbos, and a Link ECU. It makes a healthy 630 horsepower at the wheels—which it drives through a Tremec T56 and then to a Quaife LSD. Not surprisingly the factory five-speed didn’t last long at that power level. It’s more than sufficient for his needs, but this power combined with his growing comfort with the car necessitated a few upgrades in the handling, stopping, and safety departments.
First, he felt the existing bolt-in cage would no longer do with the speeds he was comfortable carrying. The talented Austin Tischler installed a rollcage. Along with that came a set of Momo seats and a fire suppression system. The interior was mostly scrapped, though most of the Buck Rogers dash was kept, and in the place of the factory gauges went an AIM display to help convey all the info from the Link ECU.
The first order of business was scrapping the so-so shocks he had on in favor of a set of Penske racing coilovers. Then, the mediocre arms were replaced with pricier SPL items. It had become clear that the 370Z brakes, though fine for street usage and light tracking, were no longer sufficient for the speeds he was carrying. The needed stopping power came from a set of Stoptech ST60 brakes with Gyrodisc rotors kept cool through a set of brake ducts made by Austin’s brother, Reno.
That mostly sorted out the issues regarding mechanical grip, but the aero hadn’t been touched yet. Steven fabricated a wooden splitter, another one of Reno’s creations, and then purchased an APR GTC300 wing for the rear, which he connected to the body with a pair of Ferrari 488 Challenge mounts.
To trim a little heft from what is a very complicated, slightly porky car, he added carbon t-tops, a fiberglass hatch, a carbon hood, and a pair of lightweight lithium batteries. In total, the Z weighs just 3,200 pounds. For a machine with two turbos, glass in the roof, rear steering (though it was removed), and an iron engine, that’s reasonably svelte.
That’s pretty much how the car’s been outfitted for the last couple years, but it’s far from complete. Steven has a new carbon hatch on the way, as well as a 3.2-liter stroker kit and a Dailey dry sump. There are some larger wheels planned as well.
Those who love Japanese turbo cars, especially those from the ‘90s, we know the Z doesn’t get the spotlight. It’s one of the tougher cars to work on and is needlessly complicated, but that was the spirit of the day back then. Despite all that, some guys stick with them; this was the car which elicited those strong responses in their formative years, after all.
It’s not like he hasn’t experienced some of the best modern supercars, but the sentimental value of this ‘90s Japanese GT has kept Steven working hard at making it into a quick and dependable track toy that can keep up with most of the Camaros, GT3s, and other modern trackday staples. There’s something touching about that.