Ode to the Hemi: A Look Back at the Legacy of Death and Glory

GURPS

INGSOC
PREMO Member
Being raised on Mopar guarantees two things. One, you have a big chip on your shoulder because Ford and Chevy get all the love. Two, the Hemi is the grease-covered idol you pray to every night. But the Hemi engine's story is one of glory and banishment.

Throughout its life, the Hemi regularly found itself on the outs. Whether it was on account of being too big, too fast, or having the rules bent against it, the Hemi had a habit of looking like a wild animal in an antique store. That perceivable personality is, of course, a huge part of the engine’s appeal. Hemis powered some cars that were sold with cartoon character stickers from the factory—that says a lot about the wacky energy the company was channeling. Its demise truly is the end of an era, as Dodge turns its attention to other means of propulsion for its legendary muscle cars.

"The Dodge Challenger and Charger are coming to an end in their current Hemi-engine-powered forms at the end of 2023. The next generation of Dodge muscle car will be a new, high-performance electric vehicle" says Dodge in an exclusive statement. Though it’s since been confirmed that the Dodge Charger will live on with an optional gas engine, a Hemi is not the powerplant of choice— at least as far as we know.

As funny as it seems, the many unjust deaths of the Hemi are part of what makes it so special. So, while the news may bog us down for a moment, it's something Dodge fans are accustomed to. All we can do is look back and admire the tragedy and triumph that is the Hemi.





 

Kyle

ULTRA-F###ING-MAGA!
PREMO Member
sad to see it go. I was never much of a Mopar fan but I always love the Hemi cars.

also, the 440s, like the GTX and Super Bee.
 

GURPS

INGSOC
PREMO Member
I always love the Hemi cars.

Hemi Mystique

Boss 429

The heart and soul of the Boss 429, you could say, is its combustion chamber design: a traditional hemi configuration, but with a twist. On a conventional hemi, Chrysler for example, the valves are deployed at right angles to the crankshaft centerline, or vertical in this photo’s orientation. But on the Boss, the valves (2.28-in intake and 1.90-in exhaust) were rotated counterclockwise around 30 degrees, mainly to improve the port angles—hence the name Twisted Hemi. Also, there were usually a pair of squish/quench zones on either side of the valves, as shown here. Some racing versions of the Boss head do not employ these compression pads, giving the chambers more of a pure hemispherical shape. Except for early prototypes and a few special castings made for nitro drag racing, all Boss heads are aluminum.

Another distinctive Boss feature: There are no head gaskets as such. Instead, a receiver groove was machined around the circumference of each cylinder (above) to accept a Cooper ring (aka WIlls ring) These rings were manufactured from hollow metal tube around .093-.096 inches in diameter, which collapsed around .016 inches when the head bolts were torqued down, sealing the cylinder and leaving a .010-in air gap between the head and the block. The sealing rings were earlier used on some British racing engines in the ’50s, and Ford tried variations of the setup on the DOHC Indy and Le Mans 427 engines before they were used on the Boss. To seal the oil and coolant passages, receivers were also machined to accept DuPont Viton O-rings. While the no-gasket system required extra care in assembly, it was essentially bulletproof.



427 Wedge SOHC

Despite the Cammer’s exotic cachet, in reality the engine was simply a two-valve, single-overhead-cam conversion of Ford’s existing 427 FE V8, and a quick and cheap one at that. Inside the company, the Cammer was known as the “90 day wonder,” a low-investment parallel project to the expensive DOHC Indy engine based on the Ford small-block V8. To save time and money on the conversion, the heads were cast iron and the cam drive was a roller chain. The oiling system was revised and to manage the greater horizontal inertia loads generated by the increased rpm, cross-bolted main caps were incorporated into the block casting. These features were then adopted on all 427 CID engines across the board.

427 Ford SOHC cam drive
 

Gilligan

#*! boat!
PREMO Member
I remember the 429 Boss but it was rarer than hens teeth.
An original Boss 429 will bring stupid money, but John Kaase has been selling reproductions for quite a few years now. They are not cheap either but nothing like what an original goes for.

I've got a 429 Super Cobra Jet engine that's stroked and bored to 533 cubic inches. Plan is to put it in one of my 17' Champ boats.
 

Kinnakeet

Well-Known Member
Hemi Mystique

Boss 429

The heart and soul of the Boss 429, you could say, is its combustion chamber design: a traditional hemi configuration, but with a twist. On a conventional hemi, Chrysler for example, the valves are deployed at right angles to the crankshaft centerline, or vertical in this photo’s orientation. But on the Boss, the valves (2.28-in intake and 1.90-in exhaust) were rotated counterclockwise around 30 degrees, mainly to improve the port angles—hence the name Twisted Hemi. Also, there were usually a pair of squish/quench zones on either side of the valves, as shown here. Some racing versions of the Boss head do not employ these compression pads, giving the chambers more of a pure hemispherical shape. Except for early prototypes and a few special castings made for nitro drag racing, all Boss heads are aluminum.

Another distinctive Boss feature: There are no head gaskets as such. Instead, a receiver groove was machined around the circumference of each cylinder (above) to accept a Cooper ring (aka WIlls ring) These rings were manufactured from hollow metal tube around .093-.096 inches in diameter, which collapsed around .016 inches when the head bolts were torqued down, sealing the cylinder and leaving a .010-in air gap between the head and the block. The sealing rings were earlier used on some British racing engines in the ’50s, and Ford tried variations of the setup on the DOHC Indy and Le Mans 427 engines before they were used on the Boss. To seal the oil and coolant passages, receivers were also machined to accept DuPont Viton O-rings. While the no-gasket system required extra care in assembly, it was essentially bulletproof.



427 Wedge SOHC

Despite the Cammer’s exotic cachet, in reality the engine was simply a two-valve, single-overhead-cam conversion of Ford’s existing 427 FE V8, and a quick and cheap one at that. Inside the company, the Cammer was known as the “90 day wonder,” a low-investment parallel project to the expensive DOHC Indy engine based on the Ford small-block V8. To save time and money on the conversion, the heads were cast iron and the cam drive was a roller chain. The oiling system was revised and to manage the greater horizontal inertia loads generated by the increased rpm, cross-bolted main caps were incorporated into the block casting. These features were then adopted on all 427 CID engines across the board.

427 Ford SOHC cam drive
429 not good for drag racing only Nascar type tracks where those massive beast could breath and live at 7500 plus
Kinda like the chevy 302
 

buddscreek

Active Member
429 not good for drag racing only Nascar type tracks where those massive beast could breath and live at 7500 plus
Kinda like the chevy 302
i remember nace mattingly running a boss 429 at potomac speedway a few times.. what a turd.. put a 427fe back into the car and could run up front. jim yates ran a 429/460 engine in a 79 fox body. that car ran damm good, mid 9's. i remember him say he didn't have 3,000. in the engine. that was in the early 80's.
 

WingsOfGold

Well-Known Member
When I think Hemi a REAL one a 392 even though I have a 5.7 now. Small block scat packs........... the 327/350 and 340 (giant killer) I had.
 
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