So, you've checked out the pictures and it's dawned on you that what you're looking at is a fully polished, all-aluminum blown Ardun engine. Pretty exciting stuff, which is exactly what we thought when Mike Herman at H&H Flatheads contacted us with news of the engine's build. H&H specializes in building performance-oriented Flatheads and supplying vintage-style speed equipment, as well as manufacturing and distributing Navarro speed equipment and S.Co.T. superchargers, but this was the first of the new aluminum block and reproduction head-equipped Arduns they'd built. New blocks and heads? Yeah, but let's rewind a little first.
Much has been written about the legendary Ardun Flathead conversion over the years-some truth, some myth, and some hearsay. A very brief history goes something like this: In 1947, years before his involvement with the Corvette, Zora Arkus-Duntov, along with his brother, Yura, designed an overhead conversion for the Ford Flathead V-8, marketing them as Ardun-an acronym of their second name, originally manufactured in New York and later assembled in England and fitted to many Allard sports cars, hence the confusing differences in the script cast into the valve covers. Whether they were or were not intended for use on Ford trucks, and whether they were or were not copied from the French Talbot design, and why they are so similar to the early Chrysler Hemi are all points that have been argued before. Likewise, the exact number of kits manufactured is up for debate, as well; for the longest time it was thought to be around 250 but now seems more like 400. Whatever, originals are rare, which explains why a select few individuals have looked into reproducing them.
What you see here, however, isn't just a pair of reproduction heads atop a Ford block but instead a brand-new, 284ci, all-aluminum improved block, reproduction Ardun heads, and vintage 4-71 blower (the only old part on the whole deal) bolted to a new manifold from Ken Austin. Yeah, you should be impressed. And, how about 382 hp at 5,300 rpm, roughly four times that of a stock Flathead? We've seen the dyno sheet, which also reveals the 396.9 lb-ft of torque produced at 4,300 rpm.
Just where did this engine come from? The story starts around a decade ago with Don Orosco, who after a lot of research and a not-inconsiderable investment, had 30 sets of Ardun heads reproduced for his personal racing efforts. Keeping three sets, he sold the remaining 27 and then sold the tooling, dies, and plans to Don Ferguson Jr. You can find out more at Don's Web site, www.ardun.com.
Though parts will interchange with originals, these new heads feature stronger rocker stands and billet aluminum roller rockers with improved geometry and internal oiling restrictors, as well as greater adjustability. The new valve springs facilitate increased valve lift, plus the lifters are an improved design over the originals. Modern 12mm spark plugs seat flush with the hemispherical chamber, meaning they'll work better with modern ignitions. It should be remembered that, although the Ardun has gained cult status over the years, the Arkus-Duntovs didn't have the money for fancy engineering and were working to a tight schedule as well as the restraints of the Ford engine block. So, there is room for a little improvement over the original design, especially taking into account the advances in technology and engineering in the intervening 60 years!
Not only has Don Ferguson continued to reproduce the heads, but he's taken the baton and run with it, the result being this high-grade 356-T6 aluminum block that now means it's possible to own a complete, brand-new Ardun engine with no old parts whatsoever. Sure, it's not cheap (really not cheap), but when was pushing the envelope ever inexpensive?
So, where's this work of art going to end up? In a '32 Vicky being put together at Roy Brizio Street Rods for Jorge Zaragoza. H&H Flatheads in La Crescenta, California, has built a number of Flatheads for Brizio, and when this one was first discussed it was intended to be a relatively simple four-carb version. Then, Jorge supplied a 4-71 blower and backplate, and the project snowballed. H&H's Mike Herman sold the four-jug inlet and pistons to another customer and supplied a set of blower pistons for Jorge. The aluminum blocks became available, and the idea of a fully polished blown engine was too good to pass up. The rest is history.
The Polishing Shop in Oxnard was responsible for the shine, H&H responsible for the incredible buildup and machining. The inlet manifold, for instance, is supplied blank, to the extent that the top has to be opened up, the mounting holes require drilling, and the pop-off valve has to be fitted, but you're going to go to Ken Austin if you want a 4-71 blower manifold for an Ardun! The blower required reconditioning, and the original Cragar snout had to be machined and fitted with new seals.
H&H put an incredible amount of work into this engine and it shows, down to details like the three individual belts driving the blower rather than one single wide belt, just to keep a nostalgic appearance. Or, the Offy crankcase breathers that required the fins on the brand-new oil pan to be carefully machined away in the area they're fitted. And, how about those aluminum water pumps? They're sourced from Australia and are now available from H&H, as indeed are all the parts mentioned in this article. There's also an exceptional amount of machining internally that was handled in-house in order to make everything work. We can't wait to see this showpiece installed and running in Jorge's Vicky.
Rod & Custom Specifications
Block
New 356 high-grade aluminium by Don Ferguson at Ardun Enterprises and polished by The Polishing Shop in Oxnard, California. Four-bolt center main cap.
Heads
Ardun Enterprises. Polished 356 grade aluminum, and 11/32-inch-stem stainless steel valves, refined combustion chambers, billet roller rockers with built-in oiling, barrel-drilled rocker shafts, small-block Chevy valve keepers, ARP head studs, and mechanical lifters. The intake and exhaust ports have been improved over original Arduns. The heads are supplied finish-machined, but with the horsepower the guys were aiming for, H&H put its own valve job in them and shimmed the springs accordingly. In fact, everything in the motor was disassembled, touched in some way, and rebuilt. While the heads are supplied ready to go, the guys at H&H went through everything.
Internals
A Scat 4-1/8-inch crank was chosen, which coupled with the 3-5/16-inch bore and custom flat-top Ross 1/8-inch over stock pistons results in a displacement of 284 ci. Scat H-beam rods were used, and H&H custom-ground a fresh camshaft using a new cam core.
Induction
Vintage 4-71 supercharger rebuilt, polished, and modified by H&H Flatheads to remove stock mounting lugs and mount from underneath with studs in the lower flange to a new Ardun-specific inlet manifold by Ken Austin. Vintage Cragar blower snout machined and rebuilt with new seals. Three new Stromberg 97 carburetors.
Ancillaries
Polished aluminum water pumps, pulley, and front cover. New finned and polished aluminum oil pan from Don Ferguson drilled for Offy crankcase breathers and fitted with aluminum baffle plate. Polished PowerGEN alternator on custom bracketry by H&H. MSD distributor.
