Boeing Engineer Builds a Wild Datsun 260Z And Creates a Company

An aerospace engineer by trade, James Taylor’s happy place is the garage on a rainy Sunday afternoon, of which there are many in the Pacific Northwest. Before he could ogle real sports cars in his garage, a poster of a Datsun 240Z on his childhood bedroom’s walls gave him something to envision in his mind’s eye.

Imagination could only keep him satisfied for so long, and soon the racing bug bit. “One colleague at Boeing encouraged me to try lapping with NASA. Karen Salvaggio and Donny Edwards got me started, really – they’d push me past my own limits regularly,” he recounted.

Within a couple months, he’d built a Nissan 350Z into an ST4 car and began competing, first in Seattle and then in Northern California when the Northwest region disbanded. “I saw these trips to California as vacations for me,” he said. “It really felt like going to see family a couple states away.”

For those four fast-paced years, he built three cars, raced them with some success, and became capable behind the wheel – capable enough to understand the platform’s limitations. “These lightweight E36 M3 Super Touring 4 cars were constantly kicking my butt. I knew the car wasn’t truly competitive there, and I did not have the budget to make the car competitive in ST3,” he explained.

That’s when a teenage dream machine provided him an opportunity to step away from wheel-to-wheel and find an arena where he might better exercise his engineering ability. When he went to inspect a Datsun 260Z hibernating under a neighbor’s tarp, he felt a twinge of ambivalence. The firewall and the floorboards had rotted out completely.

To the pessimist, it was a horror show. To Taylor, an opportunity. A lightweight, retrofitted 260Z with one of Nissan’s modern motors would fit into faster classes and challenge his burgeoning building skills. Plus, the owner’s wife was basically giving it away.

Retrofitting a Relic

As much work as he knew he had ahead of him, Taylor wasn’t worried. “With the 350Z, no matter what I did, it was never a great fit in ST4. With the 260Z, I saw an opportunity to build something unique. I wasn’t worried where it ended up.”

After considering the costs of building an RB25, he opted for the cost-effective VQ, albeit a punchier version than the one that powered his 350Z. “I know the VQs have a bad reputation, but the VQ in the old car didn’t need much other than spark plugs and oil changes. When I found a nice VQ37VHR and a matching CD009 transmission on Craigslist, it was a no-brainer.”

Any fear of blazing a new trail faded after studying the thriving aftermarket supporting the old Z. Techno Toy Tuning sold him a set of aluminum, adjustable, rose-jointed arms kit that slotted into the factory mounting points. Following those were Koni single-adjustable race dampers with Hyperco 700-pound springs at all four corners. A set of basic Wilwood big brakes provided ample braking ability for a car that weighed in at just 2,300 pounds.

The original rear had a problem with wheels coming off, which he remedied by installing Z32 300ZX Twin Turbo rear wheel bearings and half-shafts, and because he already had fitted those pieces, went ahead and installed a beefier Quaife differential for the very same model.

Taylor then welded his own plates into the chassis to adjust camber caster, and toe, and that’s what revived the rusted Z. “Suddenly, I could feel the purpose of the chassis, that it’s supposed to be an extension of the driver. Designer Yoshihiko Matsuo wanted the car-driver relationship to be that of horse and rider,” Taylor extolled.

“The car felt nimble in those tricky situations and rotated more eagerly than the 350Z. It’s like it’s telling you to put your foot down earlier than you expected. The 350Z always felt like you never had enough rear end grip, and the front liked to push, so it was tough to get to the power, which felt fine out of low-speed corners, but couldn’t pull at the end of a straight.”

Compared to the L-series it replaced, the shorter, lighter VQ helped balance what was rapidly becoming a pretty powerful car that required some weight over the driven wheels. Currently, it is counterbalanced by the 10-gallon ATL fuel cell in back, which brings the balance to 51 percent over the rear axle. With driver, the cross-weight is 50.1 percent.

When housed in a lightweight 260Z, the VQ doesn’t fall flat. With just 315 horsepower and 272 pound-feet of torque, acceleration wasn’t far off some of the heavy hitters – and more than enough for the class he chose: TT2.

During his first attempt at The Ridge Motorsports Park, Taylor reached 145 mph down the front straight, even with a big APR GT wing behind him. Clearly, he left a lot on the table that tentative first lap because he found another 10 miles an hour on the second — quick enough to run alongside a 991 GT3 RS.

Even before he attended The Ridge for his first test day, he had to mitigate the 260Z’s notorious front end lift with his first Alumalite splitter — this one measuring 40” deep and 65” wide. Heat from the motor softened the material and the aero load caused the material to flex concavely, thus bringing it closer to the ground, which it continued to strike until the splitter rods pulled through and the splitter exploded at 140 miles an hour.

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And so the iterations began: four subsequent versions with more and more aluminum stiffener plates still fell short. Frustrated, Taylor took a leap and laid up his carbon splitter with a balsa wood core, but even that had its issues.

That violent demonstration helped reify an idea by beginning a business venture. Splitters, Taylor believes, should be classed as consumables. “Splitters and endplates from the established companies are gorgeous – but let’s not think they’re pieces of jewelry,” he stated.

Cutting Composite Consumable Costs

With friend and plastics extrusion expert Jason Uemoto, the two discussed the prospect of starting a business for like-minded racers with a similar budget. The name they decided on for their fledgling business: TARR Aero.

While the classic Zs enjoy a great deal of backing, as far as aftermarket support for aero components goes, there’s not much to be found. Taylor wondered if he might be able to craft something to suit his needs since, as he says, “the offerings from the bigger brands cost too much – and racing’s barrier to entry is high enough already.”

When they started assessing what building a custom aero kit for the Z would cost, they hung their heads – making molds for carbon fiber and vacuum forming composites meant a lot of time, space, tools, and money in materials – until they got their hands on a new gadget.

While recovering from an injury, Uemoto bought a 3D printer to keep himself occupied. After a long period of trial-and-error, he acquired robust hardware, including a Dell corporate server with multiple CPUs and a quarter-terabyte of ECC RAM.

“There was this perception that 3D printing was just for making tchotchkes, but we realized that the only limiting factor is your imagination. You can do wild things with this stuff if you have the will and the way,” Uemoto said.

After experimenting with several server software packages, Uemoto chose TrueNAS for its ease of use and its support for virtual machines, which enabled him to run virtual wind tunnel software for Computational Fluid Dynamics analysis. The virtual machine is configured with Ubuntu OS and runs InsightCAE Workbench: a software package that leverages OpenFOAM to conduct CFD testing on parts, assemblies, and full vehicles. This setup excels at aerodynamic modeling and, quite crucially for a small team like theirs, avoids the costly subscription fees required by mainstream alternatives.

The dedicated server hardware provides a massive number of CPU cores and RAM to power through large modeling tests, rapidly assessing whether their iterative design changes succeed. By assigning these tasks to dedicated hardware, Uemoto can reserve his desktop’s full processing power for designing new parts. He can also configure his desktop to handle smaller CFD runs, if necessary.

Taylor, who researches new materials and their applications as part of his day job, discovered PPA-CF Core-25, a 25 percent carbon fiber-reinforced polyphthalamide filament online. PPA nylons rival carbon fiber in strength, for a quarter the cost, with only a minimal increase in weight.

“I loved the fact that it’s thermoresistant, stable, and stiff, but it was expensive at the time. Still, I tried making a few flag bases using it after all my metal bases had broken in the wind. We thought it might be overkill for what we’re doing, but after a few months without any new bases breaking, we determined it would be worthwhile.”

Uemoto first printed the outermost two inches of material and mount points, known as the hard perimeter. This element’s outer edge with integrated dovetails that would be glued together with a two-part epoxy, then make the provisions to mount the end-fences and/or splitter ramps.

Then came the interior of an enclosed cell high-density foam, but will soon be replaced by a printed product that reduces weight and increases stiffness. Secondary mount points, ramps, and end-fences came next, then were skinned in two layers of 3K twill weave carbon fiber. Following that, they tried to improve drag to lift ratio of the Z’s APR 250 wing in CFD testing.

The findings there drove the design of new endplates that increase downforce by twelve percent with a negligible increase in drag – the latter helped by the fact that no rivets or other typical joining protrusions are needed with this style of element production.

The predicted robustness was proven at their next outing at The Ridge. “Everything held up, no parts came off the car, and no mounting holes pulled through. It was way faster, too – we raised our mid corner speeds by 10 mph in Turn 6.

“With a front splitter that was actually creating downforce and new wing endplates, our top speed down the front straight at RMP was whittled down to 148mph, but our entry speed at T1 increased from 92 mph to 111 mph. That was the first time I truly felt confident taking T1 at speed, and I know there is more in it,” Taylor said.

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More than just robust and efficient, it was easy to produce. “Because we use ‘core’ material, the carbon fiber content is contained inside the core of the filament, so it doesn’t wear the printer tips as quickly as a filament with ‘random’ fiber content.”

“One downside is that PPA parts can take a long time to print. These machines don’t like to go fast. It’s not like printing polyactide, better known as PLA, which is the material people use to print statues. To make the same piece with PLA, the part would have to be much bigger and thicker to achieve the same level of stiffness,” Uemoto said.

The general objective that’s helped them refine their products over the last few years has been to reduce mass and simplify production while maintaining or improving overall stiffness. This approach led to the realization that they didn’t need to skin the element in carbon fiber once the desired stiffness was achieved with PPA-CF. That led them to wonder if the wing’s innards could be altered.

“We learned that if things go together well during the print process, and the load is distributed evenly, these pieces can carry an incredible amount of load. So why not use something stronger than high-density foam if we don’t need it?

“With 3D printing, we can build internal structures with double or triple the stiffness of foam core while reducing the weight. This keeps them from flexing, vibrating, which amount to more consistent levels of downforce. We can also create wilder designs than a mold would allow.

And all this iteration has been done to provide cost-conscious racers an affordable alternative. Predictably, much marketing money was not there with such a lean product, so in recent months, TARR has teamed up with NASA to provide members with real savings.

Now, NASA members enjoy 15 percent off the standard items like wing endplates and splitter ramps. “We hope our aero will be affordable enough to most grassroots racers – so affordable that they can afford a spare. We see these parts as consumables, and we hope our product can convince others to see things as we do.”