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The ND Miata has been around for a decade but, realistically, how can Mazda improve on it? All of today’s automotive trends—from big screen tech to electrified powertrains—run counter to the Miata’s ethos of simplicity. Mazda might be restricted by the expectations of new-car buyers and the need to satisfy regulations, but the aftermarket has free reign.
Like its predecessor generations, the ND is a great platform for modifications, and one of the best builds we’ve seen comes from Geaux Moto. Based in Louisiana, the company sells a 2.3-liter Ford EcoBoost swap kit for the ND. Naturally, Geaux Moto doesn’t leave that bigger turbocharged inline-four—used in the Mustang as well as the last Focus RS, among other things—stock. And it pairs the upgraded engine with serious aero.
Geaux Moto via YouTube
As explained in a video on the company’s YouTube channel, this car has a larger twin-scroll Garrett turbo with dual wastegates, and made 460 horsepower and 393 pound-feet of torque on the dyno (Geaux Moto’s own demo car makes a claimed 450 hp at the wheels). The customer wanted something tame enough for the street, so its regular tune is 321 hp and 378 lb-ft. The engine runs a Focus RS oil pan with added baffling, while a bigger radiator, intercooler, and supplementary radiators in the factory foglight housings handle cooling needs.
Geaux Moto uses the Mustang’s MT-82 six-speed manual transmission, which is actually the most complicated part of the swap. Installing the engine only requires some minor trimming around the cowl and movement of some accessories, but using a non-stock transmission requires an alternative to the Power Plant Frame, the ladder structure that ties the transmission to the rear differential in place of a conventional transverse crossmember. Aft of the gearbox is an OS Giken limited-slip differential in the stronger stock casing.
500HP Ecoboost ND Miata Build Break Down!
The other notable thing about this Miata is the Varis-engineered aero kit. Geaux Moto buys the enormous rear wing and builds the carbon-fiber front splitter in-house to a Varis design. The combination produces 576 pounds of downforce at 100 mph. That, along with 285/30ZR17 tires front and rear, helps keep the Miata planted as it puts down nearly twice the power of a stock ND.
This car is no laid-back cruiser, but it does retain air conditioning and most of its interior, the stock bits commingled with Sparco seats and a custom roll bar designed to fit under the DG hardtop. It all makes for an impressively well-sorted car that shows the potential of the ND chassis.
Stephen has always been passionate about cars, and managed to turn that passion into a career as a freelance automotive journalist. When he’s not handling weekend coverage for The Drive, you can find him looking for a new book to read.
