Supercharging Mazda’s New MX-5 Makes a Great Car Even Better


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“This one’s called ‘the wife-approved car,’” Brian Goodwin said as he tossed us the keys. No, he wasn’t making a joke–he really had just given us the keys to his wife’s daily commuter. And after a spirited drive on one of Southern California’s canyon roads, we’re pretty sure his wife has better taste in cars than we do.

Origin Story

Let’s get one thing out of the way early: This is not the fastest Miata we’ve ever written about. Heck, it’s probably not even the fastest Miata in this issue. It wasn’t meant to be.

The car’s owner, Andrea Mathers, is the CFO of Good-Win Racing, a Miata tuning firm that likes to push the limit. She already had plenty of really fast track cars. This one, instead, was meant to be a street car through and through–a showcase of the ultimate daily-driver Miata. Granted, this one’s more tuned to sweeping scenic routes than potholed city streets, but when you’re born and raised in SoCal, there are some habits you just can’t break.

No, Andrea and Brian didn’t start this project with the lightest model: Instead, they chose an RF with the Grand Touring package, the heaviest MX-5 you can buy. Brian figures that the power hardtop is well worth the extra hundred pounds on the highway, and if you’re going to have a cool daily, is it really that cool if you can’t hear the radio? We didn’t think so.

The most notable item on this car’s spec sheet is an Edelbrock E-Force intercooled supercharger kit. The package retails for a little less than $5000 and includes everything needed to supercharge an ND MX-5, including the tune and the CARB sticker. That’s right: Andrea’s hotrod has no issues passing California emissions tests.

Edelbrock even provides a three-year/36,000-mile warranty. No, that’s not for the supercharger–that’s for the car. If you install this kit on your new MX-5 and then blow the engine two years later, Edelbrock will pay the shop bill for a new replacement engine–plus the bill for the rental car.

The Edelbrock kit bumps rear-wheel horsepower from about 150 to just shy of 200–and that’s in CARB-legal tune with the stock exhaust manifold. Adding a RoadsterSport exhaust header–sorry, that part’s not CARB-legal–bumps horsepower at the rear wheels to about 212. Brian notes that with E85 fuel, the car has pushed past 220.

Why supercharge a daily? To, in his words, “dial up the daily driver fun level from fun yet floppy to spicy and genuinely quick for a street toy.”

The rest of the spec sheet reads like a Miata lover’s dream wishlist, with a Wilwood Dynalite big-brake kit, RoadsterSport exhaust system, underbody bracing and anti-roll bars. Koni Sport shocks are teamed with shorter bumpstops and Progress springs with rates specifically chosen for street-driven RF MX-5s. How stiff? Not too stiff, actually. The springs lower the car about an inch and raise the rates about 20 percent. Again, this particular MX-5 wasn’t built for the track, it was built for the street.

Then again, even a street car should be free to explore its performance potential, right? Also listed on the spec sheet: a Mishimoto oil cooler kit and a new grille with a significantly bigger opening. Think of these modifications like you would a first-aid kit: You may never need them, but you won’t regret having them on hand.

All told, this Miata wears more than $11,000 worth of parts from the Good-Win Racing catalog. Add that to the base price of $32,750, and a car like this would cost a little less than $44,000. That figure doesn’t include the cost of labor, but none of these upgrades are particularly hard to install at home. Even the supercharger kit is listed at just 10 hours of labor. (Of course, to save money, you can bolt the supercharger onto an early ND-chassis MX-5; we’re now seeing prices in the teens.)

How’s It Drive?

So, what’s it like to drive this souped-up street car? To give you an idea, we’re going to compare it to some honest competition: a new BMW Z4. These cars may not seem like competitors, but they’re similar on paper. Boosted four-cylinder powerplant? Check. Retractable hardtop? Check. CARB legal? Check. Even their prices are comparable: BMW lists a base MSRP of $49,700.

So, uh, yeah: We’d pick the MX-5. Despite the aftermarket supercharger, we couldn’t find a single flaw in the tune, and it really did drive like a factory-engineered, 200-wheel-horsepower car. Was it a high-horsepower screamer? No, it just felt like a normal sports car, with lots of low-end torque and plenty of top end to make things fun. Above all, it was easy to drive. That quiet exhaust really was, too, offering just the right amount of noise. Stepping on the throttle elicited a throaty exhaust note. When we stayed off the loud pedal, though, the ride was nearly as quiet as the BMW’s. That chassis brace definitely helps, too–this was one of the tightest NDs we’ve ever driven.

And on those twisty scenic roads? Forget about it. Nothing drives like a Miata, and this car would easily walk the plush Z4 when canyon carving. The springs could be a little stiffer, but then we’d probably be complaining about the rough ride instead. For this street car, the big anti-roll bars offer plenty of roll control. This comparison is mostly a contest of weight, as BMW’s roadster has really packed on the pounds since its humble Z3 days.

There is one area where the BMW wins: curb appeal. Though this MX-5 looks great, you’re never going to impress your boss with a souped-up Miata–unless your boss is Brian Goodwin. The BMW is a little quieter on the highway, too, but stay focused: Canyon roads are this MX-5’s natural habitat.

The worst part of our test drive was at the end of our trip, when we had to hand back the keys. It’s not a finely honed track car. It wasn’t mean to be. Instead, it’s a great daily driver that stands out in the parking garage–exactly what Andrea wanted.

Source

Goodwin Racing
good-win-racing.com
(858) 775-2810

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Comments
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Vigo
Vigo UltimaDork
6/27/18 1:24 p.m.

The thought of a supercharger on the updated 180hp motor really makes me wish i could get the Miata motor in the Fiat. cheeky

white_fly
white_fly Reader
6/27/18 5:09 p.m.

Right now, I wonder how a supercharged ND1 compares to a stock ND2 for the street, track and autocross. The price would be about the same for each.

te72
te72 Reader
6/28/18 10:59 p.m.

In reply to Vigo :

I still wanna see the back half of the RF mated to the front half of the Fiat... modern 240z, anyone? =)

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