ProFlo Performance-built 598-cube big-block Chev - Mill of the Month

ProFlo Performance-built combo is good for over 1000rwhp on pump E85

Big Block Chev Mill 2 B Jpg

SOME are of the opinion that there ain’t no substitute for cubic inches, while others reckon that boost makes for a handy   alternative to bulk cubage. So as the forward-thinking young sheila on the Old El Paso ad once said: “Why don’t we have both?”

Cubic inches and boost need not be mutually exclusive, and that was the thinking that ProFlo Performance applied when speccing this 598ci, 14/71-charged big-block Chevy for a ’49 Ford build that’s currently underway at the shop.

This article was first published in the December 2020 issue of Street Machine. Photos: Charlie Sant

Paul Sant from ProFlo ordered up a Dart Big M block, to which he fitted a Callies crank and rods, custom RaceTec pistons and a Camtech solid-roller camshaft, custom-ground to his specs. Heads are AFR 385 alloy items with a set of Jesel rockers driven by Trend pushrods and Crower HIPPO lifters.

The talking point, however, is the heftily proportioned Littlefield 14/71 air pump, mounted on a Littlefield manifold and topped with an Enderle Short & Ugly hat, which just peeks through the bonnet on the ’49. It lets you know what’s up without being overt or obnoxious.

598 big-block chev mill

And given that the ’49 is a street car – yep, a street car – the ProFlo team knocked up an in-house EFI system loaded with eight 2000cc injectors that works with the hat, so the big-block will have impeccable street manners as well as the ability to run on both E85 and pump fuel, as dictated by the flex-fuel sensor and Haltech Elite 2500 ECU. The Haltech will also manage the ignition side of the equation via an MSD crank trigger and an array of individual LS coil packs.

“I’ve built this exact combo twice before for other customers, so I know that it’ll make around 1030hp at the tyres on 10psi,” Paul says. “It’s a street-focused engine, so we weren’t chasing massive power; driveability was the big priority.”

A lazy 1000rwhp on pump E85 and a lowly 10psi of boost? Where do we sign?


THE belt-drive system on the engine presented some packaging challenges. The ’49 has particularly narrow rails, as it runs huge front wheels and retains full lock-to-lock steering when laid out. It didn’t help that the customer wanted air con and power steering with his blown and injected big-block, as one does…

598 big-block chev mill

It necessitated some lateral thinking, but the solution was to opt with electric power steering and water pumps, along with a custom hand-made 6pk billet drive system for the alternator and air-con compressor, and a traditional ribbed drive system for the blower. Not only does it work a treat, but it looks hot, too.

Proflo Performance,
Campbeltown, NSW


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Street Machine is the bible of Aussie modified auto culture, celebrating wild muscle cars, customs and hot rods – and the incredible humans who create them.



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