Billy Jarrell here with Today, we have the pleasure of interviewing Bronson McNemar, an avid car enthusiast and the proud owner of this monster LS Miata. Bronson’s passion for racing and his DIY approach to car modifications have gained him recognition in the automotive community. Let’s delve into his journey and discover the secrets behind his formidable Miata build.

A Passion Ignited

Bronson’s love affair with cars began at a young age when he found himself immersed in the world of competitive RC car racing. As he grew older, his interest transitioned to drag racing and Autocross. This led him to explore open tracking and competitive time attack, ultimately fueling his desire to make cars go faster.

The Mighty Miata and the Birth of BroFab

Bronson’s chosen chariot is a 2000 Mazda Miata, renowned for its agility and affordability. When asked about his preference for this particular chassis, Bronson shared his realization that Miatas were the go-to vehicles for auto-cross and road racing. Their remarkable performance-to-price ratio proved irresistible, prompting him to embark on a thrilling journey with his Mazda.

In his quest for speed, Bronson established BroFab, a small business aimed at helping fellow Miata enthusiasts enhance their vehicles’ performance. BroFab specializes in hub solutions for Miata cars and has successfully shipped over 400 sets worldwide. Bronson’s entrepreneurial endeavors serve as both a passion and a means to fund his own racing aspirations.

Conquering the Tracks

Currently, Bronson competes in various racing events, primarily associating with Gridlife and participating in their time attack track mod class. He occasionally ventures into auto-cross and even visits drag strips to quench his need for speed. Bronson’s skill and dedication have led him to achieve impressive feats, including holding the Miata-specific lap record at Mid Ohio, Pitt Race, and Summit Point. He’s also secured a commendable 3rd place finish in the Track Mod category and remains a strong contender for a top 5 spot in the current season.

LS Miata: Unleashing the Beast

Under the hood of Bronson’s LS Miata lies a powerhouse that commands attention. The car is equipped with an LS3-based 6.2L engine, boasting Individual Throttle Bodies (ITB) and an ASA cam. The transmission of choice is the Nissan CD009, while the differential hails from the Cadillac Getrag lineup. Bronson has also developed custom axles, brakes, a 3D-printed wing, and a plywood splitter, showcasing his engineering prowess.

Powering Ahead

When it comes to power adders, Bronson’s Miata relies on the ITB setup, which provides an exhilarating driving experience. Bronson takes pride in handling all aspects of the car’s MS3X Electronic Control Unit (ECU) and tuning himself. From installing to tuning and even constructing his own wiring harness, Bronson has taken DIY to the next level.

Bronson’s technical expertise extends to the engine and chassis work. He has personally executed a wide range of modifications, including the LS engine swap, exhaust system, roll cage, wiring, and even the vinyl wrap. Bronson’s hands-on approach has turned his car into a testing ground for innovative experiments.

Embracing Standalone Engine Management

Bronson’s choice of standalone engine management is the MS3X system, complemented by a Microsquirt I/O expander. The decision to opt for this setup was driven by the affordability and DIY-friendly nature of the ECM architecture. The installation process pleasantly surprised Bronson, with the MS-specific ITB mode proving exceptionally easy to tune. Within an hour, he had the car up and running, generating impressive power on the dyno. Bronson also invested significant effort in fine-tuning the Traction Control (TC) strategy, crucial for effectively utilizing the 463 whp within the confines of a small car and limited tire size.

Building his dream machine wasn’t without its hurdles. Bronson recalls the daunting task of creating the wiring harness from scratch. Additionally, he integrated an I/O expander and merged wheel speed data from a BMW MK60 ABS unit to feed all four wheel speeds to the Microsquirt. However, the challenges only fueled Bronson’s determination to overcome them and further elevate his car’s performance.

Expanding Horizons

One of the standout features of Bronson’s setup is the extensive use of available inputs and outputs (I/O) with his ECU. He records an array of data, including flex fuel levels, oil temperature and pressure, fuel pressure, and all four-wheel speeds. Looking ahead, Bronson plans to incorporate transmission and differential temperature monitoring into his setup, enhancing the overall performance and safety of his Miata.

Bronson’s technical prowess is evident in his tuning strategies. He utilizes the OEM LS crank and wheel speed sensors, wiring both ignition and injection for sequential operation. This meticulous approach ensures that the TC routine can selectively deactivate individual cylinders when necessary to tame the power output. Furthermore, Bronson’s CAN bus setup enables seamless data transmission between the MS3X and two different dashboard configurations. His primary display utilizes a Tinkerdash, while a Pi dash serves as a secondary monitor through a USB connection. To augment data acquisition in the LS Miata, Bronson incorporates a RaceCapture system, streamlining the process of capturing crucial performance metrics. Future plans include upgrading to a newer MK60E5 and leveraging the CAN bus for wheel speed readings.

Wiring Wonders

When it comes to wiring, Bronson’s journey has seen multiple iterations. Initially, he wired the MS3X to the factory Miata engine harness using a DIY BOB (Breakout Board) during the turbo 4 banger phase. However, the transition to an LS engine necessitated a flying lead harness, which provided the opportunity to streamline the wiring and tidy up the overall layout. Remarkably, Bronson even started the V8 engine on the turbo 4-cylinder tune, showcasing the adaptability of the MS3X.

Looking Ahead

In conclusion, Bronson McNemar’s LS Miata build exemplifies the spirit of automotive ingenuity and a relentless pursuit of performance. His hands-on approach, from designing and building components to wiring and tuning, showcases his deep passion for the craft. Bronson’s achievements on the track and his commitment to pushing boundaries make him an inspiring figure in the car enthusiast community. As he continues to evolve his Miata, we eagerly anticipate the next chapter in his automotive journey.