Doth Yon Conveyance Boast Hemispherical Combustion Chambers?
Published: March 6th, 2009
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The question that has haunted the very soul humanity for eons—“that thing gotta hemi?”—should hopefully drift out of the vernacular, as ChryCo is offering free Hemi V8 upgrades on every Ram 1500 they sell during “ shovel ’em out the door,” uh, make that “truck month.” So yes, good sir, it’s got a Hemi. But as Wikipedia puts it, “today, ‘hemi’ is little more than a trademark that bears little meaning, descriptively, for the engines designated as such.”
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@windswords Agreed. Don't know very much about this engine. I've driven cars with it though and yeah, it's very good. But from the little I do know it's just to heavy, so you'll never get a gas miser out of it. I think we're coming from two different directions here. The Europeans dropped it 'cause consumption is a big big issue in Europe and other parts. And Americans got to keep the Hemi 'cause gas was never much of a problem there. Lucky for you Americans! And don't get me wrong, I'd love my car to have one of these, but in these parts it just ain't going to happen.
Hemis are a good engine design that has some tech issues as displacement increases. The size of the combustion chamber results in lower flame speed compared with a wedge shaped chamber. Lower flame speed = dirty combustion, so most larger displacement hemis have two spark plugs per cylinder. Chrysler's hemi garnered most of the 1960s publicity, largely because of the NASCAR/Richard Petty affiliation. Chryslers real hp monster, however, was the 440 wedge engine, which was an awesome engine, especially in pro-stock NHRA racing. Ford brought out a 427 SOHC wedge engine in 1964 to compete against the hemi in NASCAR. It produced 657 hp out the door, before racing modifications. NASCAR banned this engine form competition, so the NASCAR Mopar hemi vs Ford sohc showdown didn't occur. The Ford engine had too much hp for the tires, brakes and aero of the NASCAR cars of that era. Anyhow, the hemi is a good engine design, but one that had some equal or better competitors.
that HEMI engine costs just as much to make as their smaller V6 engines. The WSJ had an article how successful the engine was in making Chrysler money. That free upgrade is imaginary in the sense it is just a brand name you're paying for.
People are quick to incorrectly criticise this engine as not having true hemispherical heads. In fact, the 5.7 and 6.1 Chrysler engines do have hemispherical combustion chambers. They are hemispherical, not pentroof. The only difference between this Hemi and the old Hemi are two build in small squish areas to increase air tumble in the cylinders.