This article was first published in the December 2018 issue of Street Machine

It follows the company’s mantra of chucking out the alloy block and replacing it with a good old lump of cast iron, then using the best bits from the factory combined with some choice aftermarket parts to build a bulletproof combination.

It’s a 6.0-litre LY6 truck block running a factory 5.7L crankshaft, which might sound surprising, but Warspeed founder Troy Worsley has good reason to trust it: “It got to the point where the owner’s budget stopped, but I’m a firm believer in the factory crankshaft over a cheap Chinese crank,” he says. “The Chinese ones have a design flaw in the way they’re manufactured that is quite bad, especially in a blown engine. They’re quite weak from where the front main transitions up to the first big-end.”

There’s some quality aftermarket stuff bolted to the factory crank, with Molnar power-adder rods and CP Bullet pistons. Doing the bump-and-grind is a custom cam (the specs of which Troy will only reveal are “in the 240s at .050 with lift in the .600s”) from Kelford, a Kiwi outfit that is better known for its Jap stuff. “They’ve pushed pretty hard into the LS market. We’re their biggest LS customer in Australia; we’re also the distributor for them and carry a lot of stuff on hand,” says Troy.

The heads are factory 241 castings that came off the car and have been CNC-ported by Nathan Higgins. “He’ll do the porting; then we get them back and do some more work on them,” Troy says. Warspeed even sticks to the factory head gaskets, with ARP head studs.

“We run Si valves in all our engines, and this one’s got severe-duty 2.020in intake and Inconel 1.590in exhaust valves,” Troy says. “We run a dual PAC valve-spring kit and factory rockers with a CHE trunnion kit. Once again, the factory rockers are unbelievable; they’re such a good product. LS engines have a very lightweight valvetrain, so going to a heavy-duty roller rocker is detrimental to power on an LS – they’ll lose about 300rpm and 15hp at the top end.”

The reason for the trunnion upgrade is because the stock rockers have a caged bearing with nothing holding them in place, so eventually the cage will break or shatter and the needles go through the engine – Troy has seen his fair share of mills come through the door after such a failure.

There’s a Moroso sump, but that’s been modified as well. “They don’t have an internal oil gallery to transition the oil from the front to the rear like a factory pan does,” Troy explains. “In an Australian car it becomes quite hard because the steering rack is right where the outlets on the sump are, so we weld some fittings on there to shorten it up as much as we can.”

But where it’s all happening – and where most people will be looking – is up top. The Shaun’s Custom Alloy intake is a beautiful piece of work and is fronted by a 102mm Holley Sniper throttlebody. Shaun’s also did the machining on the sleek Warspeed-designed rocker covers. “We added a few different touches like the little diamond points that come off the bolts, to give it a bit of ‘wow’ factor,” Troy says.

“The engine could make 1000hp at the wheels no issue at all, but the owner’s not in it for that; it’s going into a genuine ClubSport and he just wanted to give it some love,” Troy says. “He’s getting the engine bay smoothed and repainted and making it what he always wanted.”

With the engine all buttoned up, it’ll be shipped off to Brad Grech at Ultimate Metalworks for some fab work before heading over to Jeremy at DVS for tuning.

COSMETIC SURGERY

You have to admit, from the factory LS mills are as ugly as a box of busted spanners. To rectify this, Warspeed has done all the usual tricks – flash-looking intake, billet rocker covers and polished end plates on the heads – but it’s the finishes and bronze-and-black colour scheme that really set this engine apart. “It was a joint venture between Scotty at Oxytech and Chubb at Lowe Fabrications,” Troy says. “The billet manifold and rocker covers are anodised; the turbo compressor cover and timing cover is powdercoated. We just wanted to do something timeless and different.”