Turbo Barra-powered 1966 Ford Mustang

Can a six-cylinder Mustang still be called a muscle car? 700rwhp worth of boosted Barra says yes!


A WISE person once said that rules are meant to be broken, and Zlatko Nastoski seems to have broken his own: “I was always against fitting the Barra into a Mustang, because it’s my opinion that you can’t have a muscle car with a six-cylinder,” he says. Surely any ’Stang built with single-digit quarter-mile capabilities is beyond worthy of being called a muscle car though, even if the number of sparkplugs is less than eight!

This article was first published in the July 2019 issue of Street Machine

But we’re getting ahead of ourselves here. When Zlat returned from his honeymoon in Vegas with a fistful of folding stuff, he decided it was time to move on from VLs and Skylines and buy himself his first chrome-bumper toughie. “I was originally looking for a Camaro, but this came up and ticked all the boxes,” Zlat says. “It was a Californian car with no rust. The guy selling it didn’t want to see it go, and his kids were even hugging the car – it was pretty sad.”

Phew, that wicked orange sheet metal makes you feel warmer just looking at it, and you can bet it gives people sunburn on a nice day. No, Zlat doesn’t have a special contact at VicRoads; those plates just happened to be the next ones in the system!

Zlat likes his cars to stand out, so it wasn’t long before the ivy green paint was stripped and replaced with the fiery orange hue you see before you. The jam on this pony is eight years old, and still looks so wet it could be sticky. Most of the bodywork and prep was handled at home by Zlat, and a mate of his laid down the modified FG Falcon Sunburst Orange in a proper booth. There are no fancy body mods to be seen, just a subtle reverse-cowl and a whole bunch of polished factory brightwork. However, as you may have guessed, the gorgeous paint isn’t this pony’s only party piece.

Stuffed under that subtle bonnet bulge is a distinctly Australian piece of performance engineering: four litres’ worth of the finest twist Geelong ever produced. The Barra in Zlat’s ’Stang was dragged out of a totalled FG XR6 Turbo with a mere 30,000 clicks on it. While there’s precious little in the way of factory parts on the outside of the big six, the bottom end is completely ridgey-didge. The valve cover hides ARP head studs, Crow race valve springs and a pair of the lumpiest TBRE billet sticks available. “I made sure I got the biggest cams I could,” Zlat laughs. “They’re really aggressive, really rough, and it sounds awesome.”

Zlat wanted to make sure that no sheet metal had to be modified to cram the Barra in, which turned a straightforward engine upgrade into a far more involved endeavour. Just about every part outside the long motor was custom-made, including the 6boost exhaust manifold and the Tunnel Vision plenum. “Jason from Tunnel Vision customised one of his plenums to clear the shock tower, and he had to make sure that it didn’t restrict airflow to any cylinders,” Zlat says. “Everything’s within 10mm of everything else, and it only goes together one way.” The mill isn’t even centred in the ’bay, to allow enough room for the Garrett GTX3584RS snail and associated plumbing.

Underneath the car is a KEAS-built Powerglide and a 4000rpm TCE converter that sends power to the Mickey Thompsons through a sheet-metal nine-inch from Geelong Diffs. With only 1300-odd kilos to move around, the 1200Nm of twist the Barra puts to the pavement means acceleration in this little pony is rather rapid. “It’s a lot of fun at any speed,” says Zlat. “Even when you’re doing 110km/h on the freeway, it’ll blow the tyres off no problem!

1960s Mustang engine rooms aren’t exactly generous when you’re trying to shoehorn a monster like the Barra into them. Plumbing it neatly and legally also took a huge effort. “The exhaust was only going to be 40mm off the ground, so we made it with 4in Vibrant oval tube,” Zlat says

McDonald Bros suspension holds up every corner of the Mustang, with most of the action going on down the back end. The four-link, Viking coil-overs and custom anti-roll bar keep the rear tyres firmly planted under heavy acceleration, while Wilwood four-pots handle the job of wiping off all that speed with haste. The front end is mostly standard Ford, with more Vikings and Wilwoods to help bring the handling into the 21st century. “It’s been scaled and corner-balanced, with only a few per cent difference,” Zlat says. “The handling’s amazing; I could easily track it with some wider front wheels.”

The cockpit is a balance of form and function, with a bunch of neat TMI Products trim parts and the Billet Specialties steering wheel offset by a B&M shifter and Haltech IQ3 dash. The Scat Procar seats were lowered and shortened to prevent them ruining the car’s lines. They then had to pass ADR certification for engineering

And the best part about Zlat’s creation? It’s fully engineered, road-legal and registered. “I consulted the engineer right from the start. He only found a couple of things wrong; the seatbelts were US spec and the front wheel track wasn’t wide enough,” he says. “I’ve been pulled over and the cops just say: ‘Well done for doing it properly’.”

Apparently too much power is never enough, ’cause Zlat’s already planning a built Barra with enough berries to crack the 1000rwkW mark. “A low eight or high seven is on my bucket list. I just want to build a really fast car.” Since the engine bay’s been left untouched by the gas axe, is there any chance a V8 will find its way back in there? Zlat’s response is emphatic: “No!”


WHILE the combination of carbies, a big cam and eight pots tends to affect us car enthusiasts on a primal level, sometimes we have to admit that automotive engineering has come a long way in recent decades.

Zlat’s previous engine combo was an angry 347ci Windsor with a tunnel ram and a pair of carbs, but there’s more to a current-gen replacement than just a massive increase in torque. “I drive it every weekend and the kids love it, so the most annoying thing about the carbies was the smell and the fumes,” he says. “By the time I’d warmed it up and driven somewhere the house would stink, I’d need two showers and the kids’ eyes were watering. Now there are no fumes in the cabin and the only smell is that sweet scent of E85.”

And rubber, we’d guess!


Paint: Customised Glasurit Sunburst Orange

Mill: 4.0L Ford Barra
Induction: Tunnel Vision plenum, PWR intercooler
ECU: Haltech Barra Plug’n’Play
Turbo: GTX3584RS
Camshafts: TBRE billet
Conrods: FG turbo
Pistons: FG turbo
Crank: FG turbo
Oil pump: Billet gears
Fuel system: Two Walbro 460 pumps, 1650cc Bosch injectors, MagnaFuel reg
Cooling: Race Radiators radiator with AU thermos
Exhaust: 6boost manifold, 4in Vibrant oval-pipe exhaust, MagnaFlow muffler, Turbosmart 50mm wastegate

Gearbox: KEAS-built Powerglide, TCE Race stall converter
Converter: 4000rpm stall
Diff: Fabricated 9in, 3.55:1 gear, Truetrac, 31-spline axles

Front: Viking coil-overs
Rear: McDonald Bros four-link, Viking coil-overs, chassis connectors
Brakes: Wilwood four-pot (f & r)
Master cylinder: Wilwood manual with proportioning valve

Rims: Race Star 17×4.5 (f), Weld AlumaStar 15×8 (r)
Rubber: 175/55/17 (f), Mickey Thompson 255/60/15 (r)

Jason at Tunnel Vision; Race Parts Melbourne; McDonald Bros; my wife Danielle and my kids Zara and Zac