Join Date: Apr 2003
SIX SHOOTER XR6Turbo
Peter Luxon gets the blown XR6 to spill the best part of 300 kW.
Ever experienced one of these freak engines that, although stock, manages to hose anything else of the same make and model? Mass production on any kind of budget sees to it that such freaks of engineering exist as well as the flip-side scenario, the dud.
The root cause of such variation is production tolerances; the small differences between apparently identical parts which, if the cards fall your way, can lead to an engine that is, in the vernacular of todayís yoof, sweet. Or sick. Or fully sick. Or something.
Anyway, as well as furthering the cause of linguists, these tolerances also give engine blueprinters something to do between nine and five. The basic premise is that by optimizing all the bits and pieces, you can wind up with an engine that is slightly more than the sum of its parts. Or sweet, if you will.
And that, in a broad sweep, is whatís going on with this XR6 Turbo.
It was never a question of whether Peter Luxonís APS operation would warm up a blown BA, just when it would happen.
And now that they have, itís interesting to note that there have been no wholesale changes to hardware or big lifts in boost pressure, but rather a concentrated effort on making sure everything is optimised.
Yet the results are mind-boggling, with a huge leap in performance that truly speaks for itself and a price tag that will make you wonder if this isnít in fact, the best power-up for the buck currently available.
When we tell you that the APS XR6 has been blueprinted, weíre not talking in the traditional weight-each-piston, measure-each-conrod sense. Nope, not even the rocker cover has been lifted, the APS team instead concentrating on modifying the engine management to optimise the ignition advance curve, fuel injection and turbo behaviour. The only other fiddle has been to fit a high-flow cat, but thatís it; no bigger turbo, no bigger intercooler, not even a cold air intake. Hell, it still uses the stock air filter.
Meantime, the whole deal speaks for itself when the bullshit stops, and the dyno rollers start a-turning.
The first hurdle was to gain access to the Falconís brain. Ford has worked very hard to stop this from happening, but with many hours of slogging away at a laptop, the APS crew finally worked out what makes the XR6 tick and can now alter is parameters with a Unichip piggyback computer.
Now, we all know the limiting factor with the XR6 Turbo in manual form is that the gearbox is odds-on to explode if you go pumping more than the 450 Nm through it that the stock engine develops. Well, it will, says Luxon, if you try to boost the torque at low engine speeds when thereís a heap of load on the trannyís internals. But leave the huffing and puffing till later in the revs and you can up the ante without necessarily grenading the T5. Nothing wrong with the theory. Till it goes crunch, anyway, and it didnít while we had it.
Left standard, the Falcon blows about 6 psi of boost at about 3500 rpm and tails it off to about 5 psi between 5000 and 5500.
Respecting the gearbagís lack of fortitude, Luxon has left the boost alone below about 3000 rpm and then ramped it up to max out at around 9 psi at 3500. In the interests of reliability, it then tails off to about 7 psi at 5500 rpm, and everybodyís happy.
Meanwhile, the computer has been instructed to allow as much as eight or nine degrees of extra ignition advance at some critical points in the rev range and the fuel map has been changed to (mainly) lean things off a bit.
But what sort of numbers does it produce?
Well, consider this: On APSís rolling-road dyno, a stock XR6T with its claimed 240 kW makes about 195 kW at the wheels. The Falcon XR8 with an alleged 260 kW can muster only 180 kW at the wheels, which indicates Ford has a marketing problem hereabouts. But the Luxon XR6 Turbo makes a stunning 235 kW at the wheels, a big chunk better than either factory Falcon,
For comparisonís sake, the 300 kW HSV GTS gave 240 kW at the wheels on the same dyno. You do the math, but it indicates that the APS XR6 is probably making something like 295 kW at the crank.
Out on the road (and the dragstrip) and it feels like it, too. And then some.
On the same day (within minutes, in fact) that we ran our first sub-14 in a BA GT, Luxonís weapon scorched across the same bit of blacktop in a rousing 13.6 seconds with a terminal speed of 178.8 km/h. The first hundred came up in 5.4 seconds, and if more traction had been available, it wouldíve gone even quicker. Thatís BMW M3 quick.
Whatís really impressive is the part-throttle response out on the road. The torque wells up quick smart just like it does on the stocker but, as we said, by design the APS car doesnít feel any more muscular below about 2500 rpm. It gets interesting from there on, however.
By the time the tacho needle has swung past 3000 rpm thereís all kinds of hell breaking loose. Okay, so it doesnít exactly throw a wobbly and spit you towards the horizon, but it feels mighty strong, mighty pumped and totally together.
To say that it simply feels like a really fit XR6 Turbo is selling it sort (13.6 is walking the walk, donít forget) but thanks to the composure it shows even when tagging the limiter, thatís pretty much how it is.
And since the rest of the package from the suspension to the brakes has been left completely alone, the notion that it really is mostly stock Falcon keeps cropping up. Like, when the brakes get hot and go away after a few hard stops.
In fact, even the standard pop-off-valve has been retained, the extra boost making a bigger sneeze when you back off, but thatís all folks.
Youíll laugh at the price, meanwhile. Luxon reckons he can supply the engine management and boost tweaks for about $1,590 fitted and tuned, with another $600-$700 for the bigger cat.
Got an XR6 Turbo? Then youíve gotta have this, you really do.
Body: Four-door sedan
Engine: Front-mounted 4.0 litre 24-valve turbocharged inline six
Power: 295 kW @ 5500 rpm (est.)
Torque: 550 Nm @ 4500 rpm (est.)
Compression Ratio: 9.0:1
Bore X Stroke: 92.3 mm x 99.3 mm
Weight/Power: 5.71 kg/kW
Specific Power: 73.8 kW/litre
Transmission: Five-speed manual
Suspension: Double wishbones, coil springs, anti- roll bar, (f); control blade IRS, coil springs, anti-roll bar (r)
Length/Width/Height: 4944/1864/1444 mm
Wheelbase: 2829 mm
Track: 1553 mm (f); 1571 mm (r)
Brakes: 325 mm ventilated discs, two-piston calipers (f); 303 mm solid discs, single-piston calipers (r), ABS
Wheels: 17 x 8.0 inch, alloy
Tyres: Dunlop SP Sport, 225/45 ZR17 (f&r)
Fuel: 68 litres, PULP
Price: $46,000 approx.
0-400 13.61 @178.8 km/h