8/71-blown, mech-injected alloy LS3 combo – Mill Of The Month

While EFI has revolutionised the driveability of big, angry engines, nothing in that world can match the tough look of a mechanically injected V8 wearing a filthy, whoppin’ great blower

Photographers: Cheryl Poulson, Jacqui Dean

DAMIAN Baker from BG Engines knows this, so he has kitted out this LS3 with all the angry sauce he had in the cupboard.

First published in the May 2021 issue of Street Machine

“This is an alloy 6.2-litre LS3 that we got as a running unit,” Damo says. “It is out of 1TUFVL, and we’d done work on it in the past, but it was brought in to us for a freshen-up after the car had an incident at Powercruise and was pulled down for repairs.

“We prepared and added dual keyways to the stock LS3 crank, and also added Callies Compstar rods and 9.5:1-comp CP pistons. The cam is still a hydraulic-roller stick, but it is a custom blower-grind we spec out here at BG, and it runs on Corvette C5R lifters. I’m lucky I know some people who have a bit to do with Le Mans, and these lifters are special-order short-travel items.”

Up top, the stock #821-casting heads are basically standard except for some hand-porting, with a PAC dual spring kit. “Because the LS3 has the bigger valves in the factory heads, we leave most of that alone; that’s the beauty of these engines,” says Damo.

The 8/71 Blower Shop party-starter sits on a matching Blower Shop manifold, with a Enderle Bird hat converted to a barn-door type for a sweet old-school look that was so important to the customer. And a big part of that is the BG-designed mechanical injection set-up.

“The fuel system is done in-house, and it’s a methanol system with a custom scroll and custom jetting to run the E85,” Damo explains. “The mechanically injected E85 is something I have been doing quite a bit lately. There’s no electronic brain, as the EFI complicates it with fuel rails and injectors. This has a mechanical fuel pump mounted off the front of the engine on a Joe Blo bracket, with a ball valve up top, and that’s the fuel system.

“Everything is really straightforward with this combo. The big appeal to me is the big, blown type of tough engine without the complexity of EFI. You need a bit of experience with this type of combination to tune it, and they’re quite inefficient, but the simplicity is hands-down better over the EFI world – there’s one fuel line, just like a carby. For a Powercruise car, this is going to be far simpler than an EFI set-up. And this will be quite a Powercruise car!”

The high-riser late-model small-block is finished off with polished cylinder head caps and a pair of epic Shaun’s Custom Alloy billet rocker covers. “I like supporting Aussie products, and Shaun’s rocker covers would have to be the best ones out there for the LS,” Damo reckons. “We couldn’t stick the coil packs back on them, so the LS coils will live in the scuttle panel, with an MSD 6014 standalone control box running the ignition system.”

All up, the 6.2-litre made 888hp at 7000rpm on 15psi boost, which was where Damo was happy to cap it for the sake of the alloy block’s longevity. Tellingly, it also made 750lb-ft at 4900rpm, which will ensure 1TUFVL makes short work of the back tyres down Sydney Motorsport Park’s front straight!


We’re getting used to seeing tough street engines running dry-sump oiling systems these days, so it’s almost strange to peep the OEM oil pan living under this stout LS. “We did some internal baffling to the factory sump and modified the oil pick-up, but we didn’t need to do much to it,” Damo says. “They’re not a terrible thing, the LS sump.”

BG Engines
North Richmond, NSW