This article on Gary McRae's HSV Senator was originally published in the 2014 issue of Street Machine's LSX Tuner magazine
I COP flak for going to great lengths on ‘just’ a Commodore,” says Gary McRae of what could be Australia’s tidiest VR Senator. “I figured, what could I do to a Camaro, Mustang or Monaro that hasn’t already been done?
“For me the early HSVs were an Aussie breakthrough car, the first time something locally produced could compete against the Europeans. I took one of the best Australian late-generation muscle cars and made it better.”
Gary paid $20,000 for the then four-year-old two-owner ’93-model and initially enjoyed it as a daily driver. But when the trans let go, the Senator found itself on a slippery slope. Unloved, it copped a few years shed time then made a brief comeback as a tow car, before being rolled into a 40ft container for another five long years.
Feature: Blown 363-cube HSV VR Senator
It was out of sight but never out of mind. “I knew one day I’d do something with it,” Gary says. “Then a couple of years ago I spotted an LS3 crate motor at a good price and contacted engineer Doug Potts about the upgrade.”
From the outset, Gary worked to a master plan. “I think the term ‘sleeper’ is over-used, but I wanted a really clean Senator that when you walk around it you think, ‘Hang on, what’s going on here?’”
The body was shipped to Frank Evans-D’Angelo in Willaston for a bare-metal respray in HSV’s original hue of Anthracite with silver highlights. In the meantime, Gary was getting stuck into the transmission when the project took a significant turn.
At $4000 for the pair, plus 50 hours of Gary’s skilled CAD work, the custom-made 10-inch rear wheels are a testament to the high level of detail. “I had the front laser-scanned to within 0.1mm, from which I created a 3D CAD model,” Gary says. “I sent that to Ian Splatt from Dragway to machine the centres out of billet”
“A few months into the build I saw an LSX454 advert in Street Machine,” Gary says. “To me 454 cubes is just the ultimate. Thankfully in South Australia we don’t suffer from the weight/capacity rules like the eastern states.”
Feature: Eddy Tassone's twin-turbo VZ HSV GTO
“Every modification is reversible. I haven’t filled any holes in the engine bay and still have the original five-litre. I grew up with my family restoring cars. It doesn’t really do it for me, but I did restore the steering wheel and had the interior redone to original. That’s what’s unusual about this car. I wanted to restore it, but enhance it along the way”
Gary is a mechanical engineer and made up a new check list to handle the grunt, including strengthening the K-frame. Remaining unchanged from the original goal was that both inside and out barely hint at what’s lurking under the hood. Unless you read the number plates. Or hear the thing running. Then it’s a dead giveaway.
Featured: Callaway C4B-powered 2000 HSV VTII GTS
So let’s get to the balls of the project, all 7.4 litres of it. Atop of the Chevrolet Performance crate engine is a beautiful Jenvey manifold sporting custom-made fuel rails and Magneti Marelli IWP injectors. Gary exhaust port-matched the LS7 alloy heads, and set up the whole shebang to run on E85. The block contains forged-alloy pistons, forged-steel rods and crank, with six-bolt mains; plenty strong enough to handle a measured 507hp at the tyres.
The exhaust is also home-built. “After getting some ridiculous quotes, I bought a TIG welder, some three-inch stainless bends, tubes and mufflers and taught myself to weld,” Gary says. “I’m extremely happy with how it turned out.”
Backing up the 454 is a tough four-speed 4L65e transmission full of Sonnax goodies matched to a 3000rpm TCI Billet stall converter.
"The induction is beautiful," Gary says with some justification when you soak in this. "You just get drawn to it, which is why I custom-designed the fuel rails to match." Pulleys are Aeroflow billet, while the battery is stored int he boot keep things tidy in the bay.
“Building the gearbox was the most technically demanding aspect,” Gary says. Up the back is a Harrop 12-bolt with 3.55:1 gears and Detroit Locker. It all rides on adjustable coil-overs with a mix of lowered XYZ and King springs with beefed-up sway bars. Brakes are Wilwood calipers on drilled and slotted discs at every corner, and these sit behind the original Senator 17in five-spokes up front and custom 17x10in rims under the bum.
"If I go to 13:1 compression, up the cam from stock and add two-inch primaries, it'll be close to 750fwhp. A squirt of giggle juice could see 1000hp. My goal is to drive to the track, run a 10-second quarter and drive back. I'm not sure how easy or hard that will be"
“There’s not a part on it that’s not top-notch,” Gary says. “It took me ages. I hand-made all of my own stainless-steel brake lines, doing some three or four times until they were absolutely perfect. It’s all a bit OCD but to me that was fun.
“When I first turned the key to fire it up, I was so excited I high-fived my auto electrician! Also that first solid clunk into gear – that was a big deal for a guy who had just built his first automatic.
HSV's luxurious grey velour interior is a restoration of the original with a range of 90s niceties. The tacho has been ecalibrated and extra gauges added to keep an eye on the vital signs. Gary stuck with the original HSV cassette radio: "With a 454, who listens to the stereo?"
“I’ve seriously had so much fun building this car," he adds. "I enjoyed every minute and wouldn’t be having half the fun driving it if someone else built it. I know every nut and bolt. Apart from paint, it never left my shed.”
So what is it like to drive?
“It’s simply epic, there’s effortless torque and the throttle response is incredible,” Gary says. “My wife, who’s not into cars, went for a strap with me. At first she was impressed, expecting it to be more violent. So I hit the accelerator and fished-tailed it. She turned to me with a huge grin and said, ‘Gary, that’s just ridiculous.’ I thought she was going to punch me!”
“Next I’ll get it fully engineered. I’m about to do the brake and lane-change tests, then the chassis test. While I’ve sent Doug long and detailed engineering emails, I know there may be more changes. At the end of the day it’s all metal. I’ll just keep changing it until it’s right.”
BOX OF TRICKS
"I figured I'd have some fun building my own gearbox," Gary says of his impressive handiwork. "So I bought a 4L65e with a slipping clutch. I read a lot about it on the internet and struck up a friendship with Gregg Nader from Sonnax Industries in New York. He helped me choose and source the right parts then put me on to an auto guy in Chicago.
"It was easier than I thought, although not intuitive. First I built a rotisserie then turned up all of the tools needed on my lathe. I set up a clunker laptop out in the shed and watched a DVD from the US on how to build the 4L65. It took about six weekends.
"It was extremely satisfying. I started building it for the LS3, so the 454 may be stretching the friendshipl. But if the 'box goes pop I'll put a Tremec iin it. I've done it now, and I wouldn't build another one."
1993 VR HSV SENATOR
Induction: Jenvey EFI manifold, 60mm four-degree taper, Magneti Marelli IWP cone spray, custom fuel rail
Heads: Alloy LS7
Compression ratio: 11:1
Cam: Hydraulic roller
Pistons: Forged-alloy, 4340 forged-steel rods
Crank: 4340 forged-steel, eight-bolt flange
Oil cooler: B&M, 10AN braided lines
Water pump: Meziere electric (polished)
Ignition: Accel coil and leads, LS1 ECU with custom tune
Fuel: Weldon pump and regulator, PWM controller, dual electric E85 compatible lift pumps, Bain Racing custom alloy tank
Cooling: PWR crossflow radiator with SPAL 3000 fan
Exhaust: Pacemaker Tri-Y 1¾in, twin three-inch stainless, Di Filippo cats
Output: 507rwhp, 743lb/ft
Converter: TCI Billet 3000rpm
Diff: Harrop 12-bolt, 3.55s, Detroit Locker
Driveshafts: Gforce Level 3, Porsche turbo CVs, billet cages
Tailshaft: Hardy Spicer custom chrome-moly two-piece, Strange yokes, heavy duty centre mount
SUSPENSION & BRAKES
Springs: Lowered XYZ (f); lowered Kings (r)
Steering: Aeroflow power steering reservoir
Brakes: Cross-drilled and slotted 330mm rotors with Wilwood six-piston calipers (f); 310mm rotors with Wilwood four-piston calipers (r)
Rubber: 17/235 (f); 17/295 (r)
Rims: Senator five-spoke 17x8 (f); custom Senator replica 17x10in on Dragway centres (r)