By Alfie Bilk:
If you were seeking a guidebook on how not to carve out a career in motor sport, Greg Brown’s story might be a good starting place.
Following two years of studying numerous concepts and with a prototype partially complete, he undertook the daunting task of pioneering production Hemi cylinder heads for the small-block Ford engine in a scant period of just under four and a half months.
The processes for developing the rare Hemi included complex scanning to gather CAD data, mobilizing a casting company to create the tangible form and developing a CNC program that would sculpt its final shape. Then, a head was urgently dispatched to Jesel to develop crucial rocker development.
With an intuitive grasp of the technical and an eye for future opportunities, what had shaped Brown’s decision? “If I failed to display it at the 2016 PRI exhibition in Indianapolis, I could potentially squander a year,” he said. The performance-minded public, particularly those based in the Northeast is large and active and languishing for a further 52 weeks in obscurity was obviously not an attractive proposition. Even more astounding, word of the unique cylinder head would be released without any convincing proof of a single dyno test. There was simply no time.
When the inaugural dynamometer test of the new heads, which were attached to a 427ci World Products block, was eventually undertaken in January 2017, the results were astounding: 604hp and 601lb-ft torque. Astounding because the initial set up was meant to deliver 10.5:1 compression ratio. However, final valve changes were made, which entailed moving the intake valve seats to slightly higher territory in the combustion chamber. As a result, the original 62cc chambers had now gained 6 or 7 cubic centimeters of volume and valuable compression properties were reduced to a meager 9.8:1.
Flow details supplied by Superflow flow bench in conjunction with a 4.125in bore
LIFT INTAKE. EXHAUST
Furthermore, an out-of-the-box Edelbrock Victor Jr. intake manifold had been employed, its ports much too small when attached to the new Hemi heads. Why? “I wanted to ascertain the power output of un-ported heads when combined with an untouched intake, said Brown. A third factor that influenced the dyno sheets was the humble camshaft with duration values of 242 intake / 248 exhaust. “Getting it to 500hp is easy,” declares Brown, but generating over 600hp with low compression, un-ported heads, untouched intake and a modest camshaft is a triumph—I’m very pleased with its maiden performance”
So, what’s next? “Currently, I’m pressing ahead fulfilling orders,” he says. These include the supply of rockers, rocker stands, gaskets, etc. “But I’ve now graduated to offering pistons, rings, distributor extension and cylinder head stud or bolt kits. Also, the first competition version – which I’m working on – will feature a different compression ratio, induction system and camshaft,” says Brown.
Importantly, for this new Hemi concept to realize its full potential, it’s crucial to install it in a race car as soon as possible. This will broaden its appeal and prove its merits. Racing lives on the edge of the competition precipice and an impressive quarter-mile time slip reveals all.
Greg Brown, a 45-year-old who originated from a small town in Vermont and moved with his parents in his teenage years to Atlanta, has now based his fledgling company in the Atlanta suburb of Snellville. Twelve years ago he took employment at Jon Kaase Racing Engines, perhaps reflecting his youthful admiration for the man who has shown such versatility in a long career devoted to the development of racing engines.
Contact Greg at:
Hammerhead Performance Engines
Hammerhead’s new Hemi heads being installed for dyno-testing.
These heads are going to give the Fords that extra boost needed to compete with
those pesky LS engines when both are normally aspirated.Besides being absolutely stunning to look at they are also beautiful works of engineering. Going to follow this closely in the future. Kudos to Mr Brown!
The street rod market will be going nuts over this! The price of a street engine will be comparable to the Coyote or a lot less with a lot more cubes…maybe an Ardun-style valve cover for the purists. My mind is running overtime!
An astounding accomplishment Mr. Brown. I’ve been following this project for some time and very pleased to see the end product. It’s a magnificent piece of work. Hopefully, I’ll be able to visit your shop and get an up-close when you are ready to showcase the new heads and assorted pieces to the public. This is a great engine combination for many uses, indeed, I have a street rod project in mind. However, I’ll let you refine this unit and get your price structure sorted out before finalizing plans. Again, congratulations on your tremendous achievement. I bet John Kaase is very proud of you. /jm
Thank you guys for your kind comments. It has not been for a lack of hard work, but it’s all finally coming together. I have some very cool and interesting builds in the works with these heads, so keep checking in. You won’t be disappointed!
I will be calling for information after work today (fantastic job)
Thanks, I look forward to speaking with you.
Fantastic set of heads, this is the way Ford should have gone instead of pursuing the Coyote-style engine. The outer dimensions look about the same as the Coyote but with more cubes, and the added benefit of fewer moving parts. I would love to see a side-by-side dyno run between this engine and the Ford Coyote engine.
I have a new Edelbrock top end still in the box, and if I could sell it for what I paid, I would order your top end right now. I would be the first one to have a Hemi head 408w in a ’39 Ford pickup in Pa.
I need these heads? What kind of power are you making with turbos?
Hi. I have an X275 customer that is making over 1750 rwhp with a 412″ SBF and a single 85mm turbo on alcohol and another with a single 98mm making over 1800 rwhp on race gas.
I am looking at this and can’t help but picture the same architecture on a Harley engine…
This looks like a real nice way to roll your own Boss429.
It will be important to have the rest of the car up to the same level.
Really nice to see this. Thank You.