To recap, Muscle Garage jammed a Barra turbo six into a Holden VS Commodore ute in a quest to run a 10 for $10k. Here's what happened in part two of the build, as the Barrahore project gets ready for the dyno
This article on Muscle Garage's VS ute was originally published in the November 2017 issue of Street Machine
In part one, we gave you the rundown on Muscle Garage’s Jason Waye as he shoehorned a Ford Barra turbo inline-six into a dunger VS Commodore ute. The goal was to build a car he could take to our Street Machine Drag Challenge and run 10s for $10,000.
The plan was to take one $500 VS ute shell and fit it with a wrecking yard BA XR6T engine and auto trans. Performance mods at this stage are limited to a set of injectors, swirl pot and Bosch 044 pump, valve springs, front-mount ’cooler, enlarged flapper valve, exhaust and a tune. All for (just over) $10K all up
The South Aussie had the ute almost done except for an exhaust and the custom flash-tune in the stock XR6T ECU, along with filling it up with fresh Nulon fluids. That doesn’t mean there weren’t problems in the lead-up that tested the Muscle Garage crew’s resolve and patience.
Unlike later FG and FG X models, BA-BF Barra sumps feature the main oil well in the front, which suits the VR/VS Commodore K-frame. The later sumps feature the well at the rear, which could suit other fitments, but doesn’t work in this generation of Commodore
“We first had issues with the rear brake calipers, which were seized and so we couldn’t bleed them,” Jason says. “A quick trip to the wreckers and that was fixed, but then we discovered we had two of the neutral safety-switch wires backwards so we couldn’t get it to fire. We fixed that and the car started turning over straight away.
Chassis connectors are required for the next stage of the Barrahore build, as Jason straps on a Plazmaman intake and winds more boost in to try and push past 400kW and head for potential low-9sec passes
“We then discovered a fuel-related issue, as we couldn’t get stable pressure to the engine, and then we discovered the Bosch 044 fuel pump wasn’t plugged in, as we’d disconnected the power to the relay for when we’d primed the swirl pot. We reconnected it and it fired straight up.”
Jason got the VS down to Exhaust Technology at Kings Park in Adelaide for a free-flowing system. ‘Marky’ Mark Marcheson fabbed up a four-inch dump that reduces down to a three-inch system through a Magnaflow race muffler, then out through a standard V6 Commodore pea-shooter resonator, which actually hides a three-inch outlet for maximum sleeper points.
With the exhaust done, Jason got the VS to Graham West Workshops, where it could get a proper tune on the hub dyno. Jason had hoped for about 350kW for this first stage of the car’s build, and it actually surpassed that, recording 360kW at the hubs in the end!
“The exhaust cost more than what I’d initially expected, but I wasn’t expecting to go that large on it initially,” Jason says. “This set-up will be fine for the next stage of the car, when we really lean on it and push it up to, or past, 400rwkW.”
Initially Jason had wanted to whack a cheapo exhaust on to try and sneak under the $10K budget, but ended up putting a bigger system on to handle the 400+kW the Barrahore will be making at the treads once the new engine mods go on after Street Machine Drag Challenge
With the pipes done, the ute still needed a tune, so the Muscle Garage crew spent some time on the rollers at Graham West Workshops, where the stock, unlocked, XR6T ECU was tweaked with HP Tuners flash-tuning software.
“We had fuel issues at the dyno where it started to lean out about 3500-4000rpm,” Jason says. “It took ages to sort out, pretty much two days, and the problem was the pump in the fuel tank was too big and was pressuring the swirl pot. This boosted fuel pressure from 60psi to over 110psi, but we got it fixed and it really took off after that.”
A fuel pressure issue reared its head, as the car hadn’t copped a run at wide-open throttle at this point. Just as it came on-boost, at around 3000rpm, the ute would lean-out, which was eventually diagnosed to be fuel pressure spiking from the proper 60psi to over 110psi
Jason had hoped to make around the 350kW (470hp) mark from the force-fed twin-cam six, but he was also keen to not break the Barra for the sake of dyno-room glory.
Thankfully it all held together and the VS spat out 360kW (482hp) at the hubs.
‘Marky’ Mark Marcheson of Exhaust Technology in Kings Park, Adelaide, was handed the task of creating the exhaust for the Barrahore. A 4in dump pipe runs through a Magnaflow muffler, which runs into a 3in system back to a sneaky hidden dump tip
“To get more out of it you really need more fuel,” Jason says. “There’s a little more boost there, as we’re running 16psi but can go 18psi comfortably. I seriously think once we’ve run a 10 and done Drag Challenge we’ll put the Plazmaman intake I have here on it, wind some more boost into it, put a fuel additive into it, and crack 400-410kW.”
To maintain the sleeper look, Marky Mark at Exhaust Technology gutted the stock V6 resonator to hide the dump tip for the 3in exhaust. This way, the original weedy tailpipe still pokes out of the rear bar and no one is the wiser to the Barrahore's true potential!
With the exhaust and tune in the bag, and the required ANDRA safety items, Jason admits they squeezed the budget as far as they could, but it wasn’t quite enough. “We’ve just gone over budget, at around $10,584.
“Up to 3000rpm it drives very quietly, very subtle and lovely,” he continues. “But as soon as you get stuck into it – look out!
"I have to learn how to drive it, and that’s the big thing. Everything I’ve had has been blown cars or big V8s, where you put your foot into it and it just goes. The fly-by-wire throttle has a very short throw on it and when you stand on it, the pedal only moves 1.5 inches compared to four inches in an older car; you can’t feather it!”
With the 15in chaser wheels and stock body, there's not much to give the game away. Jason is planning to fit 235-wide radials on some custom widened chasers for drag action
Jason got to the strip to test the ute’s performance and while he had hoped to work down into a 10, the combo wasn’t quite there just yet.
“We spent Sunday at the track and had a great time,” Jason says. “It was super-consistent, but the best we could muster was a 12.04 and fastest trap speed of 118mph.”
Jason has a good idea of how he can get the ET closer to what the mph suggests the VS is capable of. “The 60ft times are woeful at 2.1, which shows us we need to up the converter and change diff gears. It is doing 5300rpm in third through the traps, still pulling like a freight train!”