Turbo LS3-powered Holden VS Commodore sleeper

This stock-looking Holden VS Commodore executive hides a 550rwkw sting in the tail from a turbo LS3

Photographers: Knackers

This article on Morgan’s VS Commodore was originally published in the Street Machine LSX Tuner magazine #8, 2018

WHILE there is a lot to love about openly aggressive street cars, sleepers are so much fun and they are popping up all over Australia as car enthusiasts discover it is sometimes better to fly under the radar. While Morgan Wise could have built a killer pro street car, his stock-looking VS Executive could fool anyone into thinking he was just another young bloke with a tidy 25-year-old car – except for the fact Morgan’s VS packs a turbo LS3 making 550rwkW, or 737rwhp in the old money!

So, what does it run? Morgan is itching to find out! “The car needs some tuning for cold start, but wide-open throttle and such is all good, and it’ll be ready to take to the track as soon as the weather improves. I was planning to debut it at the Holden Nationals, but that coincided with pulling the engine down to inspect the lifters and cam, so we missed out”

“I hadn’t owned a tough LS engine before and believed the LS3 was a stout combination to begin with,” explains Morgan. “I was familiar with the VB-VS chassis through my past experience with quick VL Turbos, and thought that a lightweight alloy V8 and turbo combo would work really well together.”

But what drew him to the VR/VS series, surely the most unloved of the Commodore platforms? Put simply, light kerb weight and a good differential.

While tidy VR/VS Commodores are rarer than chickens with lips, Morgan found a real museum piece with his. Amazingly the car hasn’t been resprayed and is in original condition!

“The VS being the last of the live-axle Commodores made it a great platform to build a high-powered street/drag car from,” Morgan says. “As this car is an Executive, it weighs around 1400kg because it doesn’t have power windows or air con and the cast-iron 5.0-litre has been removed. Plus, the amount of rear-end components available for live-axle Commodores has really boomed in the past five to 10 years.”

Though you may think finding a good, solid 23-year-old Commodore that was a factory V8 and live-axle would prove difficult, Morgan lucked out. “I bought the car from an auto electrician who purchased it from the original owner,” he says. “It was a factory 5.0-litre Executive with 140,000km and a live-axle rear-end, which is what I was looking for. I paid $5000 for it with a roadworthy certificate and 12 months’ rego.”

While Morgan hasn’t upgraded the springs, shocks or wheels yet, he has invested money in the rear end, with Whiteline adjustable upper control arms and Panhard bar added, and the lower rear arms boxed in for strength

From that point the project progressed quickly, taking a little over 18 months to get to the stage you see here.

“The car was bought in August 2016 purely with the conversion in mind,” Morgan says. “I picked the engine up in September and had the drivetrain installed by March 2017. The fabrication and wiring was finished in September; then there was ongoing tuning and troubleshooting, which was finished in March 2018.”

The engine is a Gen IV LS3, purchased as a brand-new crate motor and dropped to JCA in Ballarat, where Jason Clark stripped it, blueprinted it and balanced it up with some key upgrades. These include a VCM sump kit and Melling high-volume oil pump, with CP Bullet pistons and Spool I-beam race-series rods swinging on a stock crank. Up top, a 245/235/114 cam works LS7 lifters, chrome-moly pushrods, solid-stem extreme-duty valves and PAC dual springs.

The T4-pattern BorgWarner S482 sits on an HP Fabrications manifold, expelling excess boost through a pair of 50mm Turbosmart wastegates, while Holmes Performance custom-fitted the 450x300x130mm air-to-air intercooler to chill the intake charge. The spent gases then flow out a 3.5-inch dump pipe and down a single four-inch system with twin mufflers to keep it stealthy.

“We had some initial teething problems, including controlling boost, so a second Turbosmart 50mm wastegate was added to the crossover pipe, and boost can be controlled as needed now through the FuelTech ECU,” Morgan says. “We also found a torn diaphragm in one of the wastegates.”

The hydraulic Morel lifters packed it in almost immediately, which was recognised early on as the car didn’t make the power Morgan had expected with the previous 224/232/115 cam, so the engine was pulled down and inspected.

“It was deemed to be in good health so a set of LS7 lifters went in and an accompanying 245/235/114 camshaft,” he explains. “The power went from 470rwkW at 17psi, to 551rwkW at 13.2psi. Safe to say the old cam and lifters were the issue!”

While it’s widely accepted that E85 is the holy sauce for forced-induction builds, Morgan has experienced the shortcomings of the corn syrup before, and originally planned to use a different fuel in the VS.

While it seems like a simple build, Morgan did have some troubleshooting to do. “The car has had typical turbo LS issues associated with melting plug leads, so all the pipes were ceramic-coated, heat-wrapped and protective boots were placed over the ceramic leads,” he says. “The car also did go through two alternators in the space of 1000km, which ended up being wiring and heat-related issues burning out the regulator”

“I grew up having owned three quick street VL Turbos, two of which went low 10s down the strip. However, as Ballarat didn’t have E85 at the time, the VS came about to hopefully make bulk power on pump 98.

“During the build, E85 arrived, and so the decision was made early on to run the VS on E85. It does get terrible fuel economy, with a range of approximately 200km per tank. This definitely places it in the weekend-only use category!”

MDT built the 1200hp-rated two-speed Powerglide, sandwiched between a mild-steel two-piece tailshaft with 1350 unis, a TCI HD flexplate and Dominator’s Race Eliminator 3500rpm-stall torque converter. This isn’t the first converter Morgan had in the car, however.

“The original converter was sourced out of Texas; however, the engine developed too much torque so it wasn’t suitable and would flare badly under power,” he says. “Dominator was contacted and so far this new converter has done a great job; the car displays great wheel speed on the dyno.”

Out back, the stock BorgWarner BTR78 live-axle diff has been replaced by a much stronger Ford nine-inch, filled with a Truetrac LSD, 3.25 gears, 31-spline axles and a billet yoke.

A FuelTech FT500 ECU controls 1550cc Xspurt injectors supplied with pure E85 from a Walbro 460 in-tank pump, which sends the go-juice to a staged Holley 1800 push pump. Gigantic twin –10 feed lines then handle getting the fuel to the motor, with a single –10 return line taking the excess away

“The original LSD was pulled out before it had a chance to break,” says Morgan, who left the springs, shocks, brakes and wheels untouched.

“The whole combination is designed to go around 150mph once sorted, as the block, crank, turbo and gearbox will all begin to max out at approximately 1000hp at the engine. After track testing the standard suspension I’m hoping it should be running close to that mile-per-hour once the suspension is sorted. I’m very reluctant to put a ’cage or a parachute on it, so everything is a bit of a compromise between street and drag duties at this stage.”


Heron White

Brand: GM Gen IV LS3
Capacity: 6.2-litre
Turbo: BorgWarner S482
Intercooler: Custom 450x300x130mm air-to-air
ECU: FuelTech FT500
Pistons: CP Bullet
Rods: Spool I-beam race-series
Cam: 245/235/114
Crank: Stock
Lifters: GM Gen IV LS7
Pushrods: Chrome-moly
Fuel system: Xspurt 1550cc injectors, –10 lines, Holley 1800 pump, Walbro 460 in-tank pump
Exhaust: HP Fabrications manifold, 3.5in dump, 4in system

Gearbox: GM Powerglide, MDT valvebody
Converter: Dominator Race Eliminator 3500rpm
Diff: Ford 9in, 31-spline axles, billet yoke, Truetrac LSD, 3.25:1 gears

Front: Stock VS V8
Rear: Stock VS V8
Chassis: Whiteline Performance adjustable upper control arms, Whiteline Panhard bar, boxed lower control arms
Brakes: Stock
Master cylinder: Stock

Rims: Stock VS V8 15×7 (f & r)
Rubber: 205 radials (f), Mickey Thompson ET Radials 255/60 (r)