The Marcos Mantara LM600 Comes to Project Motor Racing

May 23, 2025

V8 Thunder, Fiberglass Fury, British Grit

In the early 2000s, a dark horse rolled out of a paddock with a nose bent like a pugilist spaceship, a soundtrack straight out of a rock(et) concert, and with about as much visibility from the cockpit as you’d ever need (if you spent most of your time with your eyes wide-shut!).

Built in a simple workshop in Westbury, the Marcos LM600 thundered onto the British GT scene with a lo-fi, big-hearted approach that left a lot of supercar manufacturers scratching their heads while chasing that ultra-wide backend.

This clearly wasn’t design by corporate committee in espresso-laced meeting rooms in Motor Valley somewhere. This was American muscle, British madness, and some serious fiberglass wizardry from one of the world’s most underrated designers.

The Rebels with a Cause

Marcos was founded in the UK in the 1950s by racer Jem Marsh (the “Mar” in Marcos) and an engineer named Frank Costin (who would also eventually become the “Cos” part of Cosworth, as well as the “Cos” part of Marcos). Marcos quickly became known for building lightweight (yes, plywood chassis was their thing back then), wildly original GT kits for drivers (like Jackie Stewart, who would take the Xylon cars to many a win) who didn’t care too much about polish, as long as they had race-winning performance under their butts.

By the 1990s, Marcos had gone bust (at least twice), been bought out (at least three times), acquired the technical staff from the recently folded TVR concern, changed their HQ to the Netherlands, and then—at the end of the century—decided “what the hell” and went full-send on GT racing, culminating in the Mantara LM600, a low-slung, wide-bodied beast built for GT racing.

The car was designed by Dutchman Wiet Huidekoper, who’d been involved in everything from the Le Mans-winning Porsche 911 GT1 ’98 program to Lola’s Group C runner to the Formula Renault 3.5 for the Formula Renault World Series (not to mention working for Reynard and Opel DTM along the way).

To qualify for GT racing homologation, Marcos built a handful of road-going LM600s. These street-legal monsters looked like nothing else on the road, complete with stretched noses, flared arches, and fighter-jet cockpits. Owning one today? Nearly impossible. They’re ultra-rare and yes, totally bonkers!

LM600 Specs: Loud, Light, and Terrifying

If you’re looking for a subtle drive, this car isn’t for you. The LM600 earned its name from its 600+ horsepower target, delivered by a 6.9L Chevrolet small-block V8 dropped into a featherweight chassis. No turbos. No assists. Just raw pushrod thunder. For Project Motor Racing, that engine has been detuned to a 5.8L V8 pushing around 480bhp to fit snugly into the N-GT class.

The LM600 was a V8 missile with flares. That ultra-light body makes it nimble, while the torque-rich V8 makes it a monster out of slow corners—a dream for elbows-out racing on tight tracks, and a nightmare for anyone who doesn’t enjoy some seriously sideways action.

The LM600 found its spiritual home in the British GT Championship, where, despite its relatively modest budget, it took the fight to some big budget giants—and won. It won in the British GT1 class with Eclipse Motorsport and Eurotech Racing in 2000 before enjoying a long shelf-life in N-GT racing.

Privateer teams continued to extract pace from the platform even as newer GT2 machinery appeared and although it never clinched a full-season title, the LM600 did what a true legend is meant to do—scored podiums, stole some improbable wins, and made diehard fans along the way with a sound that was as riotous as a post-Millwall football match from the 1990s.

The LM600 Legacy

The Marcos LM600 is a symbol of an era when GT racing was wilder, less polished, and driven by passion over polish. It’s the kind of car that came from a shed, went head-to-head with cash-rich factory programs, and scored some knockout blows.

Its silhouette was unforgettable. Its soundtrack shook paddocks. And its legacy lives on as one of the most beloved underdogs in British motorsport history. In Project Motor Racing, it comes with no electronics and no politics. Just an American V8, a fine-tuned chassis, and the will to go faster than the big boys.

If you’re a racer who appreciates a proper motorsport underdog, the LM600 brings all the noise, the fury, and the thrills with absolutely no apologies.

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