In previous articles we’ve tested the APS-enhanced XR6Ts, AVO XR6T and Nizpro
Cobra-kitted XR6T. Well, here’s another power-up package to throw into the ring
– the Redcliffe Dyno and Performance XR6T upgrade.
Steve of Redcliffe Dyno and Performance (RDP) says his upgrade packages
aren’t strictly off-the-shelf ‘kits’. Instead, each upgrade builds on a proven
platform that can be configured to suit the customer.
"Every upgrade we do is slightly different because some people want, say, a
louder exhaust or a blow-off valve. Some of the upgrades we’ve done have also
been tuned to suit normal unleaded petrol," he says.
Even more importantly, we’re told each RDP upgrade is backed by a "7 Day
Performance Challenge". The 7 Day Performance Challenge gives any potentially
unhappy customers the opportunity to have the car returned to standard within 7 days of
modification – and it won’t cost a cracker. In fact, you’re even allowed to keep
the RDP replacement lower grille for your troubles.
So let’s take a look at what’s on offer.
There are two platform upgrades available – the 300kW and 360kW
The basic 300kW upgrade relies primarily on a RDP piggy-back computer
(previously known as the TSI computer). A K&N drop-in panel air filter is
also included. This upgrade – which provides 25 percent more power than stock -
The 360kW upgrade (as driven) adds a replacement exhaust, boost control
solenoid, upgrade injectors and replacement spark plugs. This upgrade – which
provides a 50 percent power gain – costs AUD$7500.
RDP replaces the factory XR6T exhaust system with a single 3 inch mandrel
bent job employing a straight-through centre resonator and muffler.
Interestingly, the cat converter is from a GM LS1 V8 – it seems an odd choice, but
Steve has the flow bench figures to back his decision. Steve also prefers to
construct the system from mild steel – he says stainless pipe causes a ringing
noise through the system. But if you absolutely must have stainless,
well, you can have it at extra cost...
The air intake system retains the factory airbox equipped with a K&N
filter. Steve says the K&N is generally worth a couple of kilowatts extra. A
SS Inductions cold air intake is also available to customers at extra cost.
Steve tells us the factory XR6T fuel system starts to run out of puff at more
than about 330kW so it’s no surprise his 360kW upgrade incorporates upgrade
injectors. RDP offers a choice of high-flowed standard injectors (rated at
445cc) or replacement Bosch ‘green’ injectors. Steve prefers the high-flowed
stock injectors because they maintain a factory under-bonnet appearance.
For outputs beyond 360kW, a Bosch Motorsport pump is fitted in the fuel tank.
A booster fuel pump (controlled by a spare output of the RDP piggy-back
computer) can be added for extreme power applications.
The RDP piggy-back computer is different to most add-on systems we’ve seen on
XR6Ts because it controls the injectors directly from an in-built injector
driver. The injector driver can operate high or low impedance injectors and
avoids ‘Check Engine’ light troubles that are apparently common with other
approaches. The timing of the Ford direct-fire ignition arrangement is also
controlled by the RDP computer. Note that the spark plugs are swapped to
Split-Fire items – we’re told by RDP the standard plugs "blow out" at high boost
The RDP piggy-back computer is tuned in real-time on the chassis dyno and
offers a data logging facility and two auxiliary outputs (which can be used to
trigger a shift light, intercooler water spray, nitrous injection or an
auxiliary fuel pump). The RDP computer is also employed to increase turbo boost
to around 12 psi with the help of a high-flow replacement solenoid. The RDP
computer also clamps the original ECU’s MAP signal to avoid hitting a boost cut.
Note that Steve says the factory air-to-air intercooler reaches its effective
limit when you try for more than about 360kW. The intercooler remains stock
in this upgrade but is protected by a RDP replacement lower grille (which also
adds a sportier look).
In this mechanical configuration, the RDP test mule – a 2002 XR6T automatic
with a fresh crate engine - develops 396hp (291kW) at the wheels on the in-house
Dyno Dynamics chassis dyno. Note, however, the cat converter had been punched
out for RDP testing purposes - as a result, this ATW figure is slightly
optimistic. In any case, Steve says all of the XR6T enhancements they’ve done
achieve more power than claimed – 360kW at the engine is conservative.
As seen in this graph, boost pressure is smoothly controlled to around 12 psi
and there’s generous mid-range, which should mean plenty of useable on-road
Let’s hit the road and find out!
The RDP-enhanced XR6T starts like a standard Falcon. Idle quality is good but
probably not as smooth a factory. Note, however, the RDP computer provided only
semi-sequential injection at the time of our test while the current models
fully-sequential operation; Steve says this improves the idle to factory
Put your foot down and the RDP XR6T offers noticeably sharper throttle
response than standard - but it’s not really sharp. From this point, you
can ride an effortless wave of mid-range grunt that builds and builds. The auto
transmission of our test car was unaltered but up-shifts feel more aggressive as
the RDP piggy-back computer holds constant boost during the shift; we’re told
the factory computer reduces boost pressure during the transition.
We also found the exhaust system too loud when we drove the car – something
Steve assures us is the result of the cat converter being punched out for
testing. There was also an annoying fluttering noise from a rising rate fuel
pressure regulator, which had been fitted for RDP testing. (We were assured
mixtures were the same as normally achived with the standard regulator, so there
was no performance advantage with the different pressure regulator).
And how hard does she go? Well, it’s easy to become blasé but it feels just
like a 396hp (291kW) ATW XR6T should. We were unable to conduct performance
testing but the car has recorded an 11.86 second quarter mile in this
configuration (using Nitto race tyres).
If you want a tailored upgrade with the assurance of a money-back guarantee,
the RDP upgrade is well worth a look. What have you got to lose?
Redcliffe Dyno and Performance +61 7 3284 1925
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