Pumped Muscle

We have a lot to thank centrifugal superchargers for. Back when they became popular in Australia during the mid ‘90s, they turned the traditional V8 performance scene on its head - what had previously been considered a ‘fast’ V8 changed almost overnight. Well, apply those same principles to a current-generation multi-valve Ford V8 and the result is pretty obvious – it's one awesome combo.

If you ever needed convincing, check out this machine - Brett X’s recently acquired Ford BA XR8 ute.

Brett purchased this vehicle virtually as you see it a few months ago from Redcliffe Performance and Dyno. Before arriving in Brett’s hands, the car had served as Redcliffe Dyno’s test vehicle.

“It was my dream car since I first saw it, so when Steve from Redcliffe said it was for sale I couldn’t let it go,” says Brett.

As you’ve probably twigged, this fearsome Ford runs a supercharger kit to achieve its monster power output.

Not long after taking delivery of their then-new new Boss 260 powered XR8 ute, Redcliffe Dyno got stuck into the car with a free-flow exhaust system. The car uses a pair of Herrod extractors and a twin 2 ½ inch mandrel pipe set-up that was designed and fabricated in-house. One of the big attractions is the twin ‘shotgun’ pipes hanging out the rear – these let you know when you’ve been smoked!

Next came the latest V2-SQ Vortech centrifugal supercharger which was installed using some off-the-shelf parts such as a water injection, a flexible pre-compressor intake pipe and a Bosch blow-off valve. Redcliffe Dyno modified an existing supercharger mounting bracket and ran their own pulley and belt system – we’re told it’s guaranteed not to slip.

For the engine management, a RPD (Redliffe Performance and Dyno) interceptor is employed. The RPD interceptor contains a 22 psi MAP sensor and an in-built injector driver – unlike most interceptors, this device drives the injectors directly. And what injectors are they, you ask? High-flow versions of the standard parts teamed with an additional Bosch Motorsport 033 pump and Malpassi regulator.

In this configuration, Redcliffe Dyno saw the car generating up to 433kW at the wheels – around 600kW at the flywheel! This was measured on the company’s in-house Dyno Dynamics chassis dyno and with a substantial 15 psi boost. Steve from Redcliffe makes the point you can’t reliably ask that much of the stock engine for an extended period – the standard rods and pistons will inevitably go ‘bang’. Boosting it to 15 psi simply showed what could be achieved at high boost. The stock compression ratio of the Boss 260 is 9.4:1.

The standard suspension was also modified while at Redcliffe Dyno. A set of King Super Low springs lower the body to the point where, as Brett says, the car rides on its arse – it’s a set-up aimed at show more than go.

A set of high-quality aftermarket brake pads also went in to complement the factory ABS brakes.

And that’s pretty much how the car arrived in Brett’s hands. The only change was boost pressure was eased to a more conservative 10.8 psi and, as a result, power slipped back to around 313kW at the treads – still almost double the factory output...

Not one to sit on his hands, Brett has since returned the car to Redcliffe for installation of a CAPA Stage 3 water-to-air intercooler kit. This kit comprises compact heat-exchange core, front radiator, a pair of electric water pumps, reservoir and replacement induction plumbing. The addition of an intercooler is a very wise move in terms of performance and engine longevity. We can only guess that power has increased beyond 313kW at the wheels but, at the time of writing, the car was yet to return to the chassis dyno.

Brett isn’t one to get sucked in to dyno figures.

“It’s my toy for the street,” says Brett. And it’s a simple as that.

This street focus is the reason why Brett recently went for an upgraded 11 inch full-face clutch in preference to a dual-plater. Sure, a dual-plate clutch can handle greater load but, unless you plan to regularly run the car down the quarter mile on a grippy set of slick tyres, there’s no need. The 5 speed gearbox remains standard except for a Herrod short-shift mechanism, which reduces throw by around 40 percent.

The factory option 3.46:1 LSD rear gives improved acceleration compared to the conventional 3.23:1 ratio.

Inside, the trim remains standard XR-spec with the addition of Redcliffe’s gauge pod which, in this case, contains a pair of 20 psi boost gauges. These gauges are configured to show the pressure drop through the intercooler core – you’re talking approximately 1 psi at the current power level. A Rockford Fosgate amplifier and 10 inch Earthquake sub (mounted behind passenger seat) provide a boost to the factory audio system.

And what are those killer wheels? US-sourced Boyd Coddington 18s wearing 235/40 and 255/45 high-performance rubber. The polished rims are a great match for the factory high-impact orange paint.

The bonnet is a Redcliffe Dyno all-fibreglass item which lets out a lot of under-bonnet heat soak in traffic conditions. This photo shows the twin forward-facing NACA ducts and the reversed air outlet. Note that the reversed outlet sits on top of the engine’s intake plenum to give the famous Ford ‘shaker’ effect. The front bumper also employs a Redcliffe lower grille and the XR8 badge on the tailgate has a ‘Supercharged’ badge added below.

And those customized ’39.0KW’ number plates?

Well, 390kW ATW is the magic figure Brett’s shooting for. However, to achieve this while maintaining good reliability the engine will inevitably need aftermarket rods and pistons.

Ahhh, the dream never ends!

Contact: Redcliffe Performance and Dyno +61 7 3284 1925