The best cars are the ones that get used. Driven. Hooned. Appreciated as the functional objects that they are. That’s why it’s impossible to look at Luis Millan’s well-loved turbo widebody 1990 Mazda Miata and not smile a little. This is how you do track cars right, and importantly, how to do it on a budget like a boss.
Luis acquired his Miata nine years ago for just $1,000 and the trade of an old first-gen GoPro, which definitely set the tone for the rest of his build. It wasn’t his first choice for a race car, but the Miata was the it-car for some of the classes he ran with.
Now that the car has won a few National Auto Sport Association Northeast and Motorsports Northeast titles and even competed in a round of Global Time Attack, though, I can tell Luis is making the most of it.
Best of all, it’s not pretty. It’s not polished. Many of the parts came from friends, trades, take-offs and other sources on the cheap. Others were homemade custom touches, like the wooden splitter (complete with wood stain!) and the big ol’ ain’t-care hole in the hood. This car exists for one purpose and one purpose only: fun.
Millan’s Miata was initially purchased as a back-up track beater, with 180,000 miles on the clock. It was meant to be something fun, but cheap to mess around with. He had dreams of building up a Nissan 240SX, but he noticed that the oh-so-common Miatas had grip for days and were leaving him in the dust at autocross events.
The car then became Luis’ multipurpose hoon-tool, doing everything from grocery runs to track days. Eventually, he became an instructor with NASA, and moved into doing time trials with the car.
The well-loved $50 stock engine from a 1992 Miata that Luis had in the car needed a bit more power, so Millan picked up a menagerie of go-fast parts from the part-outs of one friend’s turbo Miata and another’s supercharged Miata.
On went a Garrett GT2554R turbo with an internal wastegate, Inconel turbo hardware, Synapse Engineering Synchronic blow-off valve, MiataRoadster exhaust manifold hardware, and a Begi cast turbo manifold. A Hallman manual boost controller was set to 12 psi—not too much, but enough to jolt you into the back of the Miata’s ultra-light Kirkey racing seats.
A Track Dog Racing high-mount intercooler kit from the supercharged car was also modified to fit Millan’s turbo setup.
The car was converted to a coil-on-plug ignition system that uses Corolla coil packs, which delivers the higher voltage a forced-induction engine needs. It was tuned by Xenocron to run on 93-octane pump gas using a Megasquirt MSPNP2 ECU. The new setup also used a Wells TPS210 Variable Throttle Position Sensor in place of the fairly simple stock Mazda one, and an Innovate LC-1 wideband O2 sensor controller to control the air-fuel ratio.
An ATP Turbo V-Band downpipe adapter along with a custom 2.5-inch turbo-back exhaust was added, which had two resonators instead of a muffler that gave the exhaust note its sound. A K&N cone filter went on the intake elbow to the compressor intake.
Because the Miata’s iron-block, non-interference 1.6-liter engines are so cheap, stout and plentiful, Luis didn’t feel as if he needed to dig into the engine internals to turbocharge it.
Any time you crack into an engine’s internals and start replacing parts, the cost of your build tends to go up exponentially, so Luis just didn’t. After all, if he kills the engine, it will probably just be $50 again somewhere for a new one.
He did, however, glitter powder coat the valve cover to match the uprights of the rear wing. It’s fun—why not?
Millan also replaced the valve stem seals and added a JPM oil pan baffle to alleviate some oil burn and prevent oil starvation in turns, respectively. AWR’s stiffer 95-durometer motor mounts now hold it all in place.
The higher-capacity 1.8-liter Miata gas tank was also added to fuel it all, along with 420cc fuel injectors meant for a Mazda RX-8 and a Walbro 255 fuel pump.
The transmission also hasn’t received much tweaking, as it’s still the stock Miata five-speed manual. Millan added an F1 Racing lightweight flywheel and six-puck spring clutch, plus an ACT HD pressure plate. The car has a 4.3 Torsen limited-slip differential mounted on urethane diff mounts, so there’s no sad one-tire fire burnouts here.
Likewise, the cooling system was reworked to handle the upgrades. We can all see the big hole in the hood, of course. A Supermiata crossflow radiator also went up front, along with two ECU-controlled Mishimoto fans. A carbon fiber upper radiator diverter panel and an LRB Speed aluminum undertray both help send air straight to that radiator.
An M-Tuned coolant reroute kit also undid some of the compromises Mazda made with cooling the Miata engine when they turned an existing transverse engine design ninety degrees for use in the Miata. That switcheroo made coolant flow backwards in the Miata from how it was originally designed for Mazda’s transverse cars, and makes the front of the Miata engine run hotter as a result. This kit relocated the thermostat and made the coolant flow as it was originally intended from back to front, so the stock thermostat housing in the front of the engine was removed and blocked off as a result.
Braking was also beefed up to compensate for the extra speed in the form of Flyin’ Miata’s Little Big Brake Kit. That included four-piston Wilwood calipers at all corners, Hawk DTC-30 brake pads, ATE racing brake fluid and a Wilwood proportioning valve that lets him adjust the brake balance of the car. Those bigger calipers got some extra cooling as well, thanks to a Track Speed Engineering Singular Motorsports brake duct kit.
A tweak in NASA’s time trials rules soon allowed Luis to run a massive 66.5-inch carbon fiber Kognition Design rear wing, which was even serial number 002 from the company. It had been sitting in his cubicle for a couple years, waiting to be used. The revised rules then allowed competitors to run rear wings that were as wide as their cars.
“That wing is for a 240[SX]—it was too wide,” Millan told Jalopnik. “So, what’s the next best thing? Make the car wider.”
So, on went the wing on glitter powder coated Garage Star chassis mounts along with a widebody kit from Autokonexion, the front of which came from a friend’s basement, and the rear had been hiding in an attic.
Autokonexion’s Adore NA/NC front bumper was added to complete the look. Garage Star steering rack spacers and urethane steering rack bushings helped add extra width and feel to the front axle.
Luis also has two sets of 15x9 wheels for depending on the use: Advanti Storm S1 wheels with used 225/45R15 Hoosier R7 tires for autocross and track days, and TR Motorsports wheels with 245/40R15 tires (usually either Maxxis VR1s or Hankook RS4s) for pretty much any use he wants to throw at them.
Something needed to stick the front of the car down more now that the rear had a bit more downforce sucking it to the ground, so on went a custom splitter. Splitters are almost always disposable, so Luis used a material that would be easy to re-cut and re-make should his splitter get damaged in action: half-inch-thick birch plywood, attached with custom-made mounts. Dark walnut deck stain was applied to the wood to make it look pretty, of course.
“I don’t want a two [or] three-hundred dollar piece of carbon or whatever in front of my car,” Millan explained. “This was $20.”
Along those lines, Millan refers to his home-built air dam as coming from “Home Depot Racing.”
Several other items on the outside of the Miata were added or modified for total track domination, including the addition of an original Mazda hardtop with a Lexan rear window, a half-cut rear bumper, LRB Speed rear finish panel, Flyin’ Miata front tow hook and carbon fiber rear-view mirrors.
Lexan vented front quarter windows also help blow air into the cabin on hot days.
A Hard Dog M1 Sport double diagonal roll bar was installed, along with a Hard Dog bolt-in harness bar that keeps the shoulder belts of the car’s Schroth six-point harnesses in place.
Most of the actual money that was spent on this car was on suspension mods, as that’s really what defines how the car drives. Supermiata Xida single-adjustable coilovers with spherical billet mounts, Hyperco springs and helper springs went on, along with polyurethane bushings, a Racing Beat front sway bar with brace kit, 14-mm rear sway bar, and 949 Racing end links.
“Turbo’s cool, but to me, power is an afterthought,” Millan said. “Being able to pick on high-horsepower cars when you have a little piece of crap is amazing,” he continued.
It wasn’t all additions, though. Much of the joy of the car is in what’s been left out, both under the hood and inside the bare-bones cabin. The parking brake, HVAC system and interior carpets were all removed. Additional, unused wires were trimmed out of the dashboard harness.
“I wanted simplicity, so everything I didn’t need was removed,” Luis said.
As someone who because race car’d her own headlights into the shed (whoops!), that is extremely my aesthetic. Luis’ Miata now has over 300,000 miles on it, and there’s plenty more to come.
Grip tape was added on the floorboards to keep you from slipping on the bare metal floor and pedals. LRB Speed aluminum door cards, a detachable Oreca 2R steering wheel and a wide-angle rear-view mirror were some of the key things that make it livable inside. The steering column was lowered by about an inch, and the short-shifter also has a 1320 shift knob extender and a leather shift knob from a Mitsubishi 3000GT.
Glowshift gauges complete with a shift light, a data acquisition system and custom warning lights are there on the dash. Of course, there’s still a sound system so he doesn’t go too nuts in there.
Perhaps most importantly, Millan noted that “most, if not all, bolts and nuts turned by myself or friends over beers and good times.”
Luis estimates that he as around $11,000 in the car after the initial purchase as it sits, spread over nine years of ownership. Part of that is due to the nature of part-outs and the money you can recoup on widely used existing parts. The two kits he used to turbocharge the car were close to $11,000 on their own, but Luis was able to sell off around $6,000 of the naturally aspirated parts he’d no longer need to make back a big chunk of the out-of-pocket cost, bringing the total cost of turbo-ing the car back down to around $5,000 or so.
Parts for Miatas are also mercifully inexpensive, with the brand-new coilovers ringing in around $2300, and the brakes close to $900. All in all, for less than most mid-pack Spec Miata builds, Luis has something a bit faster that he’s truly made into his own.
Look, if you had told me that one of my favorite builds from this series would be a Miata, I wouldn’t have believed you. There’s just so many Miatas. They’re the Pumpkin Spice Latte of sports cars, and like Starbucks’ most trendy creation, it’s just not for me.
Yet it’s hard not to get caught up in someone else’s enthusiasm for a car, especially when that energy is channeled into making the car into something truly unique that’s faster, sillier and more fun to drive. This car makes all the right noises, has all the right aerodynamic mods, and even has glittery parts, yet it’s not too precious. There’s nothing holding you back from driving the crap out of a car like this.
When given the choice between a fancy car you don’t even want to park under a tree for fear of acorn damage and a beater, trust me: always take the beater.
We’re featuring the coolest project cars from across the internet on Build of the Week—some of which now even make it on video! What insane build have you been wrenching on lately? Seen any good build threads we should know about? Drop me a line at stef dot schrader at jalopnik dot com with “Build of the Week” somewhere in the subject line if you’d like to be featured here.