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Celebrating 15 Years of Ford's Barra Engine

From a supercharged concept to its final iteration in the FG X Sprint 6, this is the definitive story of Australia’s greatest engine.

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It’s easy, in 2017, to think of ourselves as a V8 nation.

V8s in local performance cars were once everywhere. Still are (but you’re shopping second-hand now). They won Bathurst. They created brands like HDT, HSV and FPV. There couldn’t be a single lover of home-grown performance cars that doesn’t love the V8.

However, here’s the rub. If you look back far enough, we’re also a six-cylinder tribe. Six bangers also won Bathurst – they provided Peter Brock with his first Mount Panorama victory. A six-pot (the EH S4) was the first Bathurst homologation special. The VL Commodore Turbo was the first local car to put ‘unleaded petrol’ and ‘performance’ into the same sentence.

 If we’re talking about local performance six-cylinder cars, then none come close to scaling the same dynamic or cultural heights as Ford’s magnificent XR6 Turbo. I’m no fan of absolutes, but I am game to say the blown Barra six is the best locally developed engine ever to come out of this wide, brown land. And, believe it or not, we’ve now been living with the legend for a full 15 years. A decade-and-a-half of six-pot excellence, is how I look at it. And I know I’m not the only one.

Cars like the XR6T don’t come along every day. They couldn’t possibly, not when you talk to the people who were there and you begin to understand how it all happened. But, like most brilliant achievements, the XR6T was the brainchild not of a committee or industry think-tank, but of a handful of enthusiasts. And leading that very small handful was a bloke called Gordon Barfield.

 Back around the turn of the century, Gordon was working as the program manager for Tickford (and later, when it morphed, FPV). The new BA Falcon was waiting in the wings, and with it came that new, four-valve, DOHC six-cylinder engine. Barfield knew that this new six was a fabulous thing and offered a great opportunity for Tickford to create something special for the Ford customer who neither needed, or wanted, a V8 performance Falcon. So Barfield started lobbying for something to be made of it.

“Yes, the XR6 Turbo’ was my baby,” he admits, with no small hint of pride in his voice. “During the development of the four-valve six-cylinder, we (at Tickford) were saying, What are we going to do with this thing? How do we go forward? We could modify the engine and we might have got five kilowatts, but that wasn’t going to do it.”

As Tickford grew into FPV, the late, great Howard Marsden joined the planning team, and Howard’s instincts told him that a supercharged version of the Barra six would be a good thing. The problem was that the Barra project was already too far down the development track to be adapted to a supercharged application, and Barfield knew it.

“We couldn’t upset the existing architecture, the front-end drive (the belts and pulleys and such) so a supercharger was out. In fact, a supercharger would have put the development program back months. Howard had his eye on a Sprintex supercharger, but I said to him, ‘No, that isn’t going to work’.”

 So Barfield started thinking laterally. He’d been watching the trend from Swedish makers Saab and Volvo in adapting low-pressure turbochargers to their engines with some good results. The low-pressure installations meant low levels of turbo lag and no real negative effect on reliability or longevity.

“Also, nobody (from the engineering department) was really making a grab for the real estate around the exhaust manifold – it’s too hot, obviously – so getting a turbocharger to fit wasn’t a huge problem. No, the problem was getting an intercooler to fit into the existing packaging. Luckily, our design principle was for a low-boost turbo on an engine that was already a high-torque unit, so we could get away with a smaller intercooler; one that fitted down low and out of the way.” The engineering, though, was the easy bit.

 With the basics of the design sketched up, the next hurdle for the project was to get Ford’s notoriously conservative management to go for it. “Winning over the Ford brass wasn’t easy because the BA Falcon (in the light of the AU disaster) was a big deal. Going for a new, high-performance model was a pretty brave move. It took quite a bit of balls from management. And any deal we struck to make the project happen involved having the turbo fitted on the line at Geelong, not offline somewhere else.”

Ultimately, though, the XR6 Turbo project gained the support of Ford president at the time, Geoff Polites, and, crucially, engineering chief Trevor Worthington.

“I spoke to Trevor and he was really supportive. He could see the need for a model like this and also that there was nowhere else to go for a performance six.” Marketing was next and while plenty of punters could see everything that was right about the XR6T, that’s never enough at boardroom level. Eventually, though, the project was green-lighted, partly on the basis that with the low-boost nature of the thing, there was headroom for FPV to do more with the engine (and ultimately create the F6) as time passed and really build it into a performance dynasty. Which is exactly what happened (check the XR6T timeline). Let’s see how it all happened.

 The first XR6 Turbo, the BA model came along at a time when Ford was trying to make everybody forget about the disaster that had been the AU Falcon of 1998. A couple of speedy AU facelifts helped with damage control, but it wasn’t really until 2002’s BA Falcon that the slate was anywhere near being wiped clean. Clearly, the BA was an important car; if Ford got it wrong again, it could just about forget the whole thing and go back to building Capris and Lasers. Luckily, with the BA, Ford Oz got it very right.

A large part of that rightness was an all-new DOHC, four-valve version of the Falcon 4.0-litre six. And by the time the Broady brains trust had got done with it, it was sporting a Garrett GT33/40R snail, bigger injectors and a lower, 8.7:1 compression ratio thanks to different pistons. Power leapt from the N/A Barra’s 182kW to 240kW and torque now maxxed out at 450Nm. And if you cross-reference those numbers with the Ford three and four-valve V8s offered at the same time, you’ll see that the blown Barra gave the three-valve a power (if not torque) hiding and the four-valve XR8 motor a big scare. Makes you wonder if Ford wasn’t pulling a few punches on the power output front to avoid any nasty comparisons, too.

 The new blown six was only available in an XR6 Turbo; you couldn’t have it in a Fairmont or a taxi-pack Falc. But, cleverly, Ford did do an XR6T version of the BA Ute and that was about as popular as a ute ever got. Beyond that, you could have your turbo with either the four-speed auto or five-speed manual and stuff like leather was optional.

The auto was the nicer car, but either way, the XR6T had, from the moment showroom doors opened on the first morning, rewritten the book on six-pot poke.

From that point, the Turbo’s progress was one of refinement and improvement and the fact that it remained a strong seller right up until Ford Oz pulled the plug on local manufacturing back in late 2016, proves just what a star it was. The first of those improvements came with the BA Series II in 2004 when the XR6T got a six-speed manual to replace the old T5, but it wasn’t until the BF model in 2005 that the four-speed auto was replaced by a new six-speed ZF unit. Power also got a kick up the bum at this point to 245kW and torque was now 480Nm. But the improved gearing meant that even though performance was up, so was fuel economy. Win-win.

 The biggest underbonnet changes came with the BF Series II in 2006 when the turbo-six’s bottom end was replaced by the version FPV had been using in the F6 Typhoon from as far back as 2004. That meant stronger valve springs (which had always been the engine’s Achilles heel) and the tougher con-rods from the LPG version of the Barra six.

If that was the bottom end the car had always been crying out for, in 2008 with the launch of the FG Falcon, the XR6T also got the snail it had been waiting for. While the early design used a big turbo to keep boost happening at high revs, that also made it a bit laggy. The smaller unit fitted to the FG version reduced that lag while better engine management kept it boosting longer. Power was now 270kW and torque was a much beefier 533Nm.

As a thank you note to those of us who had fallen in love with the blown Barra all those years ago, Ford used the very last Falcon, the FG X, to present us with the best XR6T ever. Dubbed the Sprint (there was an XR8 Sprint, too) the final iteration of the whole concept combined the best bits for a whopping 325kW and 576Nm.

Talk about saving the best till last.

Key Points to Look for When Buying a Barra

Right, about now, you’re probably thinking: yep, I need me an XR6 Turbo. Catch is, of course, that you’ll be buying a car that somebody else has thrashed before you. That said, they’re pretty damn tough, and there’s a wealth of knowledge out there that can predict what’s going to go bang.

 Pretty much any XR6 Turbo with its share of kays on board will almost certainly be ready for new spark plugs and coils. Unless the seller can show you proof that these have been done recently, budget for replacements. The factory iridium spark plugs cost a bomb, but the hack is to use a ‘normal’ plug and re-gap it a bit smaller. But when it comes to coil-packs, the experts we talked to reckon the ones with the factory part numbers are the only way to go.

All XR6Ts are hard on their diff bushes, too, so check them for play and check the service book. Ideally, the previous head-banger has changed the oil and filter at 10,000km intervals, not the 15,000 ones listed in the handbook. Sludgy oil can eventually block the oil feed to the turbocharger which then starves and fails.

Early XR6Ts experienced the odd piston failure, but it was rare and running changes fixed it. Valve springs were also a bit underdone in those early cars and intake gaskets could fail. A lot of cars were left with no go when the cam-angle sensor wire in behind the cylinder head got cooked over time, became brittle and snapped. It’s a common fault. Stock brakes on the XR6T were seriously underdone and would warp on a warm day. Aftermarket replacements are needed.

 The six-speed automatic introduced with the BF can cause a few headaches, too. Apparently, sand and swarf from the engine-block casting process can find its way into the car’s cooling system and shot-peen the thin transmission cooling pipes. At that point, coolant gets into the transmission ruining the bearings and the electronics. Not good.

Centre-bearings in the tail-shaft were always a bit of a problem, too, but the fusion-welded tail-shaft that came in with the FG model is also a bit prone to twisting. A conventionally welded replacement tail-shaft from an earlier model is the go. The FG’s turbo pipe was also notoriously thin in places (due to core-shift in the casting process). The world is full of viable replacements.

David Morley

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