Australia's Mustang magician: Melbourne's Herrod Performance follows a simple recipe

It was the ‘K-Code’ Mustang that started it all, just a few months after the 1964 launch of Ford’s original Pony car.

Starting with a standard V8-powered Mustang, Ford’s performance wizards beefed up the standard four-barrel 157kW/407Nm 289ci (4.7-litre) small-block V8 with a swag of add-ons that lifted outputs to 202kW and 423Nm.

Here, suddenly, was a true muscle car, one that combined high outputs with light weight (the K-Code Mustangs weighed between 1270kg and 1400kg depending on body style and fitted options) to deliver true street performance.

That opened the floodgates for hi-po upgrades, with famed US designer and tinkerer Carroll Shelby – and his legendary GT350 and GT500 – the early poster children for hot Mustangs.

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Fast forward to today, and the business of performance enhancing drugs for America’s favourite sportscar is booming, including right here in Australia.

Herrod Performance has established itself as one of the pre-eminent Mustang specialists, not just here in Australia, but around the world.

Fronted by Rob Herrod, whose CV reads like a catalogue of Blue Oval muscle car magic, the Melbourne-based outfit has designed and developed a range of go-faster bits for the Mustang that elevate what is an already fearsome beast into something else altogether. That his company does so in collaboration with, and the blessing of, Ford in the US is the icing on the cake.

Herrod Performance will work its magic on the entire Mustang line-up from 2015 onwards, including the four-cylinder EcoBoost. But it’s for his work today on the already fearsome Mustang Dark Horse that Herrod is best-known. Oh, and his collaboration with Ford on the Australian-market only Mustang R-Spec that brought supercharging to the Blue Oval’s halo Pony car for a balls-out 522kW and 827Nm, all wrapped in a Ford-approved and warranted package and with the approval of the Australian Government.

It’s that same supercharged recipe underpinning Herrod’s work on the Mustang Dark Horse today.
It’s a simple recipe, but complex in its execution. Herrod didn’t want to be just another ‘aftermarket’ tuner when he turned his attention to making Fords go faster. Working closely with Ford Performance in the US, and with the rubber-stamping of the Australian government, Herrod Performance has become a bona-fide manufacturer in its own right.

“We’re actually regarded as a manufacturer by the Australian government,” Herrod explains, adding that every new Mustang GT or Dark Horse that enters his Melbourne factory, leaves as a registered, fully compliant, ADR-approved Herrod Mustang.

But let’s rewind just a little to look at some numbers. When the Mustang Dark Horse leaves the Ford factory in Flat Rock, Michigan, its atmo V8 is good for an already impressive 350kW and 550Nm. Of course, there’s an argument that with only a meagre power bump over the regular GT’s 345kW/550Nm, the Dark Horse underdelivers on its $20,000 premium.

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But that’s to miss the point – the Dark Horse more than just squeezing extra horses out of the thumping Coyote 5.0-litre V8 lurking under the bonnet. A new manual transmission and 3:73.1 diff bring shorter ratios, making better use of available torque than the regular GT ever could. And with a handling package turned for the racetrack, the Dark Horse is a serious car for track day warriors.

But the greater argument is that you can never have too much power, and it’s here where Herrod
Performance steps up to the plate with its catalogue of Ford Performance-approved upgrades that make the 350kW of the already formidable Dark Horse seem a little quaint.

How much power? Try 604kW, or 810 horsepower in the old language. So how exactly does Herrod Performance weave its horsepower magic? By supercharging, of course.
It’s the headline act in what Herrod calls its

Mustang GT and Dark Horse Compliance Package, a name that offers little hint of the beastliness
contained within its spec sheet. Let’s break it down.

The Supercharger

Manufactured by Whipple in the US, and approved and calibrated by Ford Performance for use in its Mustang range, the 3.0L blower features an inverted twin-screw design, 92mm throttle body and dual pass intercooler, the latter – as its name suggests – cooling the blown air twice to improve density, and thus performance.

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An advanced air intake system promotes the free flow of air through twin filters into the 120mm supercharger inlet. The unimpeded airflow and improved airspeed helps to extract maximum power from the supercharger.

The net result of all this forced induction artistry is a monstrous 604kW and 867Nm, a significant bump over the regular Mustang GT’s 345kW/570Nm.

The Exhaust

The denser, more compressed air forced into the Coyote V8’s cylinders requires a higher fuel burn to extract more power and meatier torque that are the hallmarks of supercharging.

But more fuel being burnt comes at cost, and we’re not just talking at the petrol bowser. Using more fuel creates more exhaust gasses, and higher emissions are frowned upon by regulators. Herrod solved this regulatory problem by designing a new exhaust system that meets the Australian government’s stringent ADR on emissions.

“We work with a company in the US called Borla who manufactures all the exhaust systems for Ford Racing,” Herrod tells Wheels. “But they don’t have any in their catalogue that meet Australian Design Rules. So we had to develop our own exhaust system to suit that.”

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The Herrod Performance-branded system, expertly crafted from 2.5-inch stainless steel tubing, is a work of art. It connects directly onto the Mustang’s stock catalytic converters and uses the original factory-installed exhaust mounts.

The mufflers too, are Herrod branded, leading to four black-chrome exhaust tips embossed with the Blue Oval logo. They look stunning.

Best of all, says Herrod, the new system is compatible with the Dark Horse’s bimodal setup – quiet, normal, sport and track – meaning there’s no loss of sound quality. If anything, the addition of some in-house built open airboxes enhances the Dark Horse’s soundtrack giving it, according to Herrod, “a real sporty racing feel, a little bit of extra induction noise”. And who doesn’t love more noise from their muscle car?

And it has, of course, been designed to meet “Australian ADR; the stationary noise test, drive-by noise, all that stuff. It wasn’t easy,” admits Herrod.

The Suspension

Another in-house design feature is the lowered spring kit designed specifically to suit the suspension geometry of the S650 series Mustang, including Dark Horse.

The progressive-rate springs, finished in a striking blue colour, lower the Dark Horse’s ride height by 20mm up front and 25mm at the rear, lending the Mustang an aggressive stance on the road. Herrod will also recalibrate the standard-fit Magneride adaptive suspension on Dark Horse models to accommodate the new springs and lowered ride height.

But as Herrod explains, more than just an aesthetic addition, the Australian manufactured springs “give the car a much better ride, and a lot better handling. We also upgrade the stabiliser bars as well.”

The result is improved cornering stability, a reduction in body roll but without compromising on ride comfort.

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The Wheels

The stunning 20-inch Bronze wheels that adorn the Dark Horse in these photos have been designed by Herrod himself. They’re shod in Michelin Pilot Sport 4S rubber, 285/30/R20 up front and 305/30R20 at the rear.

Herrod Performance fits new tyre pressure monitoring sensors while the wheels are compatible with the factory issued Mustang centre caps and wheel nuts. Showing Herrod’s commitment to detail, the tyre placard located on the B-pillar door jamb has been updated to reflect the new wheel and tyre sizes.
For buyers who think Bronze isn’t the right fit for their paintwork, the same design is also available in traditional silver.

The Wing

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Not a Herrod Performance part, but straight out of the Ford Performance catalogue.

“It’s an OEM product,” says Herrod. “It’s from the Dark Horse Handling Package. It’s a better wing than what comes standard in the car.”

It features an integrated Gurney flap, similar to the one found on the Ford GT supercar. More than just for show, the wing improves downforce.

The Warranty

Herrod is proud of his long association with Ford Performance, a relationship spanning decades that has seen the Melbourne-based outfit collect several Ford Performance top 10 dealer awards over the years.

But perhaps the Blue Oval’s biggest acknowledgment of Herrod’s engineering integrity and commitment to the brand comes in the form of a full Ford Racing warranty for every Herrod Mustang that rolls out of his Thomastown facility.

“I’m very anal about making sure that what the Herrod brand sells to the new car market is 100 per cent roadworthy and legal…

“We cover the warranty – three years and 60,000km – and it’s a Herrod/Ford Racing warranty.”

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The Price

Prices vary for the Mustang GT and Dark Horse Compliance Package but GT owners should budget for around $30,000, while Dark Horse owners can expect to pay a smidgeon more, largely due to the extra work required to calibrate that car’s Magneride adaptive suspension setup.

The Compliance Package includes the Ford Performance Supercharger Kit, Herrod Performance exhaust system, lowered suspension as well as Herrod badging and a custom build number plaque.

Not included are extra goodies such as the wheels and tyres, rear wing, and a host of other ancillary components, like those illustrated on these pages. All up, the Herrod Performance upgrades of our photo car cost around $40,000.

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As for how long it takes to complete the transformation? Herrod says his team of technicians can turn around a car in about three days.

The end result is a stunning machine, one that captures the spirit of the original hi-po Mustang in a thoroughly modern way. And it’s made right here in Australia.

This story first appeared in the August 2026 issue of Wheels magazine, now on sale. Subscribe here and gain access to 12 issues for $109 plus online access to every Wheels issue since 1953.