1000hp Sonny’s big-block-powered LX hatch

Rob took one of Australia’s most iconic muscle cars and stuffed it with 1050hp of all-motor thump

Photographers: Ben Hosking

The age-old saying goes that there ain’t no substitute for cubic inches, and with 615ci worth of Sonny’s Racing Engines fat-block on board his LX Torana hatch, it’s a theory that Sydney bloke Rob clearly subscribes to.

First published in Street Machine’s Yearbook 2023

Rob’s previous toy, a VL Calais that we featured in Street Machine LSX Tuner #5, was also an all-motor affair, packing an LSX454R, which at the time was GM’s gnarliest crate engine. Rob was quite content with the Calais, and rightly so, but peer pressure can be a powerful thing.

“We were at Summernats in 2017 when my best mate, John Saad, got a phone call asking if he knew anyone who might be interested in a Torana hatchback,” Rob recalls. “Over the weekend, the boys were geeing me up to buy the Torana. On the way home, we stopped to look at it, and it turned out to be a car my mate’s cousins built back in 2000. I’d watched it get built, and 17 years on, I had an opportunity to buy it. I couldn’t say no.”

Rob immediately booked the hatch in with JT Performance for a quick birthday – some mini-tubs, a new set of wheels and a switch to E85. But peer pressure again played a part, and things soon escalated.

“John called and told me he could get a 615ci big-block Chev from Sonny’s at a good price,” Rob says. “I told him he was crazy and there was no chance, but when I hung up, my brain went into overdrive. I called him back 20 minutes later and said, ‘You know what? Order it.’ I decided that I wanted to go all-out and build one of the best hatchbacks in the country.”

Sonny’s Racing is best known for building mega-cube mountain motors, and while Rob’s engine is one of Sonny’s pump-fuel street-car combos, that doesn’t mean it’s not proper tough. It’s built using a Dart Big-M block, Manley rods and custom Sonny’s pistons, topped with SAR/Brodix ‘Pro Stock’ 14.5-degree alloy heads with T&D shaft-mounted rockers. The Sonny’s tunnel ram intake is topped with twin AED 1150 carbs, and it’s good for a proven 1050hp on the engine dyno.

Naturally, you can’t just drop a 1050hp, 615ci fatty in your Torana and call it a day, so the brief to JT Performance expanded significantly with the move to the new motor. Michael at JT stripped the car down to a shell and placed it on a jig ready for surgery, before Chris from CS Engineering tackled the fab work.

Chris built the custom front end and engine plates to anchor the big-block, modified the tunnel and firewall, and raised the floor 65mm so there was enough real estate for a twin four-inch exhaust system without compromising on ride height. He also tubbed the car for 20×13 Simmons wheels and built the nine-inch rear end, which sports 4.11:1 gears, a full spool and meaty 40-spline axles, suspended by Strange coil-overs.

The bodywork was then handled by John Raso, while Danny and the team at Custom Bodyworks cooked up a custom-mixed blue and lovingly layered it onto the panels.

In the cabin, there’s a decidedly retro vibe, with the trim handled by Daniel at Unique Marine & Auto Upholstery. “I wanted the old-school pro street look, so I went for a 90s interior theme with Recaro seats, Auto Meter gauges, a CD player and a Momo steering wheel,” Rob explains. There’s also a six-point rollcage and an Al’s Race Glides shifter controlling the Turbo 400 transmission.

The finishing touches and final fit-up were handled by the crew at JT Performance, and while Rob is yet to venture down the strip with the car, it has managed to pull some silverware at a few shows, including Top Pro Modified on debut at Meguiar’s MotorEx in 2022.

“The feedback since the car has been finished has been crazy; people love it and appreciate all the work that’s gone into it,” says Rob. “It was a five-year build, and it’s been well worth it, but I’m hanging my boots up now until my son RJ turns 18. I’ll build one more car for him and that’s it – I’m done. This car was built from me to him, and when he’s a bit older, I’ll build something with him as a father-and-son project.”

On the subject of Rob’s young ’uns, he has three of them, and they all love cruising in the hatch. “One of the best things about this car is that my kids love it and share the same passion as myself for cars,” he said. “The only problem is that with three kids and a two-seater car, it’s a lot of stops and starts, so they can have a turn each on a Sunday.”

Sounds like Rob might have to come out of retirement and build a family cruiser!


Paint:Custom Blue
Brand:Sonny’s Race Engines 615ci big-block Chev
Induction:Twin 1150cfm AED carbs, Sonny’s tunnel ram
Heads:SAR/Brodix Pro Stock 14.5-degree aluminium heads, Manley valves
Camshaft:SAR custom roller camshaft
Conrods:Manley steel rods
Pistons:Sonny’s custom pistons with tool-steel wrist pins
Crank:4340 internally balanced
Oil pump:Internal Moroso billet pump, Moroso oil pan
Fuel system:MagnaFuel ProStar 500
Cooling:PWR custom radiator, 16in thermo fans
Exhaust:2.25in headers, twin 4in exhaust, Hooker mufflers
Ignition:MSD crank trigger distributor
Gearbox:Turbo 400, billet internals
Diff:9in, 40-spline Mark Williams axles, 4.11:1 gears, full spool
Front:Custom arms, Viking coil-overs
Rear:Four-link, Strange coil-overs
Brakes:Wilwood discs and six-piston calipers (f), Wilwood discs and two-piston calipers (r)
Master cylinder:Wilwood
Rims:Simmons FR; 20×7 (f), 20×13 (r)
Rubber:Toyo 225/35R20 (f), Mickey Thompson 29×15.00R20 (r)

Michael at JT Performance; Chris at CS Engineering; John Raso for the bodywork; Danny, AJ and the team at Custom Bodyworks for the paint; Daniel at Unique Marine & Auto Upholstery; Mark at Ontrak Auto Electrical; Adept Metal Polishing; Scotty at Oxytech; Sam and the boys at Tempe Tyres; Muscle Car Parts; Rocket Industries; Danny Tran for the killer dash resto and help throughout the build, Alex (Moose) for maintaining the car’s clean appearance; John Saad and TJ for helping me out every step of the way; last but not least, my dad for all his help and always having my back, my fiancée Belinda and kids Savanna, Sienna and Robbie (aka RJ).