While a bunch of Blue Oval engines have earned their stripes as street-and-strip maulers over the years, the old 5.4-litre modular V8 wasn’t one of them. Sure, they make some low-end torque, but they’re also bulky, which has deterred a lot of street machiners from retrofitting them.

First published in the September 2024 issue of Street Machine

They were predominantly a truck motor in the USA, with a 4.6-litre version being widely used in passenger cars. But when Ford Australia was looking to re-power some of its family sedans in the post-Windsor era, the company plumped for the 5.4 instead. Available in Australia with either three-valve SOHC or four-valve DOHC heads, the stock 5.4 Boss was probably Ford’s equivalent of the old GM 253 thong-slapper: plenty of bark, but not a lot of bite.

However, Sydney home builder Joe Russo, owner of the BA FPV GT you see here, has another story to tell. Thanks to the efforts of Sydney’s Autotech Engineering, Joe’s 5.4-powered rocket ship makes north of 1000hp, and the best part is that turning the mill into an LS-destroyer was as simple as throwing some good-quality engine parts and boost at it, and watching jaws drop.

Joe bought the FPV around 20 years ago, but it didn’t take long before he was looking for a bit more punch, so he asked Autotech Engineering’s then-owner, Spiro Papadimatos, to get the ball rolling. Spiro got to work on an eight-throttlebody aspo version of the Boss, which was good for around 500hp.

Eventually, though, Joe still wanted more, so he went back to Autotech and asked the team to overhaul the 5.4 for boost. The brief was for a tough street car that wasn’t a lag monster; something that would blow the tyres off on the crack of the loud pedal. Given the BA now boasts twin turbos and a supercharger, it’s fair to say Joe has ended up with a fair bit more than he asked for!

“This thing is just mental to drive,” says Autotech Engineering’s current owner, Tyson Munro. “With the compound boost set-up, it makes crazy power; you can stand on it at 3000rpm and have 30psi of boost instantly.”

Plenty of twin-boosted combos over the years have ultimately ended up being more show than go, but the boys at Autotech were confident that twin turbos feeding a 2.3-litre Yella Terra blower would tip the scales.

The build kicked off with the 5.4 block getting sent to Jeff Ramsay Engineering to be fire-ringed for big boost, using a copper head gasket.

The factory crank has been retained but now swings Callies Ultra I-beam conrods with CP pistons. The mill has been ARP-studded from top to bottom, while a set of four-valve heads were treated to a port job and fitted with Manley valves and springs. A custom cam package was designed in-house, with an MMR Navigator chain and tensioner assembly added to the mix.

As with most late-model Ford motors, a billet oil pump gearset was needed, and the engine retains the stock oil pan.

The 46mm steampipe turbo manifolds mount the twin GTX3584RS turbos (with Turbosmart wastegates) behind the headlights. The rear exhaust wheels have been stepped up to give the combo the top-end power it needs when the supercharger starts to run out of legs. The turbos have 3.5-inch dump pipes running into a single 4.5-inch stainless exhaust system.

“We wanted to go with the 2.3-litre blower to give us that instant, low-end punch that you need on the street,” Tyson explains. “We have really only installed a running-in tune-up for Joe to get a handle on the car, but at 26psi and 6000rpm, it’s right around 1000hp at the tyres, and by the time it gets to 30psi and 8000, you can add another couple of hundred to that.”

With the static compression at 10:1, this 5.4 can happily chug regular unleaded, but with flex-fuel, things can get spicy on E85.

As far as electronics go, Joe has spared no expense, employing the latest Haltech Nexus R5 with all the bells and whistles, including the iC-7 dash and keypad.

It’s pretty busy under the bonnet, so Tyson and the team put plenty of effort into making things tidier and more compact, with attention paid to component detailing. With the engine needing bulk fuel at full noise, there’s a serious fuel system fitted, with triple Walbro 525 pumps installed in the factory tank and a two-litre surge tank plumbed in –8 all the way forward to a Turbosmart fuel pressure regulator.

The intake system is pretty straightforward, with the twin turbos blowing through an intercooler and feeding into the blower’s bypass valve. The 2.3-litre air pump itself swings off an ATI balancer, while a water-to-air intercooler with an interchiller helps keep the heat down via the factory air-conditioning system. Even at full noise, intake temps barely tip 30 degrees.

The car still retains the factory T56 six-speed gearbox, but the clutch has been upgraded to a custom-built twin-plate. To handle the extra mumbo, the factory independent rear end now runs a Ford Motorsport diff with a Wavetrac LSD, and all the bushes were replaced with urethane items.

“It just makes stupid power whenever you want it,” Tyson says of the combo. “But if you don’t want bushfires, we have the Nexus R5 set up with traction control.”

One thing’s for sure: in the right hands, the old 5.4 can be made into a hell of a weapon!