These days, it’s tempting to think of traditional engine platforms like the Windsor and Cleveland small-blocks as being dated, known quantities, eclipsed by more modern powerhouses like the Barra and 7.3-litre Godzilla. However, enterprising engine builders like Bill Kaglatzis from BK Racing Engines in Sydney are still pushing the limits of what’s possible from a naturally aspirated, carburettor-fed, pushrod small-block.

“This one started its life as our 800hp package, but we gave it the normal BK lemon twist, so it actually does 823hp at 7800rpm, and 611lb-ft at 6300rpm,” Bill says of the Dart-based, 433ci combo you see here.

The Dart block runs a Scat 4340 crank, Compstar rods and 12:1-comp Diamond pistons, making for a solid bottom end. A custom BK solid-roller stick works bushed BAM .905in lifters, Smith Brothers pushrods, and T&D Pro Series alloy rockers, while PSI ML springs, Del West retainers, and stainless Victory valves round out the valvetrain.

“It has all the fruit,” Bill says. “To make it live at this power level and rpm, you need these parts to be absolutely top-shelf quality.”

One area where the BK team have continued to find gains is the cylinder heads, with this combo wearing Aussie Higgins items.

“We normally use Nathan Higgins’s 2.8in cross-section SBF heads on these packages, which gets us to the 800hp range, but we realised we were using all that head could give us,” Bill explains. “With this build, Nathan gave us a slightly larger head at 3.0in cross-section, which isn’t the biggest port, but it’s bigger than the 2.8. This resulted in a gain of 23hp for a small $500 upgrade in cost.”

The heads have been matched to a tall Higgins single-plane manifold, crowned by a billet APD twin-blade carb that flows around 1200cfm. “It looks like two big barn doors in the carb instead of four smaller throttles,” explains Bill. “These twin-blade carbs flow huge air but fit on the more common 4150-pattern manifolds.”

An ICE distributor sends the lightning Express Post, while a Meziere electric water pump, Romac balancer and Rollmaster timing chain dress the front of the angry SBF. Despite making over 820hp, the Clevor wears a wet sump system and a traditional Melling Select oil pump.

“This engine is going into an XB Falcon street car that will do a bit of everything,” says Bill. “While it makes peak power at nearly 8000rpm, it can do highway miles, but you won’t go driving it to Queensland. It’ll do everything else, though.

“Fifteen years ago, 700hp engines were hard to start, fumey, and fouled plugs on start-up,” Bill continues. “This engine fires straight up and is happy on the street, even though it isn’t EFI. People look at carburettors and think nothing has changed, but the carburettor has evolved, and they’re a great option for these types of engines.”

PANNING FOR GOLD

The enormous front-sump oil pan is one of BK’s in-house products, developed through years of motorsport R&D. “We’ve raced a lot of Falcons for many years, and it’s always a challenge to keep them alive with a front sump,” says Bill. “We built a pan for one of our 1000hp small-block Falcons, and what we learned from that engine, we put into the design of all our oil pans. This design with the kick-out will probably make 10-12hp over any off-the-shelf Falcon pan.”

BK Race Engines
Bankstown, NSW
bkraceengines.com.au