Why Dodge Didn't Ditch Pushrod V8s For Dohc Engines

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Much of nan Dodge's modern occurrence tin beryllium attributed to thundering Hemi V8s nether nan hood of nan Challenger, Charger, and different models. Likewise, overmuch of nan logic for its floundering income coming is owed to nan determination of former Stellantis CEO Carlos Tavares to termination nan Hemi V8 alongside the musculus cars it powered that defined nan brand's identity.

The cars that launched this surge of occurrence person immoderate amazingly aged underpinnings. The LX level these cars rode connected was based connected a 1990s Mercedes-Benz E-Class, though it was thoroughly updated complete time. Similarly, Hemi V8s are old-fashioned pushrod engines, not modern dual overhead cam (DOHC) designs for illustration nan Ford Coyote 5.0 that powers nan Mustang GT.

In hindsight, it's clear that these were beardown choices for Dodge and its musculus car lineup. Still, nan mobility remains — why did Dodge instrumentality pinch pushrod V8s, a creation which nan institution first introduced successful nan Firepower V8 measurement backmost successful 1951? The reply comes down to respective factors that made this creation celebrated successful nan original musculus car era and stay conscionable arsenic applicable coming arsenic they were backmost then.

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For a musculus car to sell, it has to thrust one. That intends providing gobs of tire-smoking torque alternatively than putting each nan eggs into nan horsepower basket. 

Since horsepower is nan consequence of torque multiplied by motor speed, a small, low-torque motor for illustration nan Honda S2000 tin still nutrient important horsepower numbers by revving to almost 9,000 RPM. The replacement is to favour nan different broadside of nan equation by keeping nan RPMs down and maximizing torque. This is wherever nan pushrod V8 shines. While its creation prevents it from achieving precocious RPMs, a large V8 tin still move a batch of aerial conscionable because of its ample size.

Another facet that is simply a disadvantage for horsepower but an advantage for torque is that nan Hemi V8 only has 2 valves per cylinder, not 4 for illustration astir DOHC engines. This limits airflow and horsepower astatine precocious RPMs, but since a pushrod V8 can't do precocious RPMs anyway, that's not an issue. Instead, this regularisation increases nan velocity of aerial flowing into nan cylinders. This causes nan aerial and substance to operation much effectively, combust much efficiently, and nutrient much torque.

Of course, just because it's a small harder to make large horsepower from a pushrod Hemi V8 doesn't mean it can't beryllium done.

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While musculus car torque was a large logic for keeping nan pushrod V8, location were different factors arsenic well. For starters, it's a comparatively elemental creation with a azygous camshaft that drives nan full valvetrain, alternatively than 4 successful a DOHC V8. That besides eliminates respective gears and timing belts aliases chains. The azygous timing concatenation is rather short, since nan camshaft is correct adjacent to nan crankshaft. This creation besides intends that upgrading to a hotter cam involves replacing 1 camshaft alternatively of four, which is some easier and little expensive. 

Eliminating nan other complexity of a DOHC V8 besides reduces nan engine's weight. It makes nan motor smaller arsenic well – peculiarly nan heads. They only request to incorporate nan pushrods, rockers, and valves alternatively of the full valvetrain, camshafts and all, for illustration a DOHC engine. This makes nan motor easier to fresh nether nan hood, some successful nan vehicles they're intended for arsenic good arsenic different cars that they whitethorn (almost) fresh into, such arsenic this audacious Hellcat Miata. 

The last use of nan pushrod V8 is its cost, arsenic it is simply little costly to build than a DOHC V8. If this tin prevention nan shaper moreover a fewer 100 bucks per engine, it adds up to a important savings crossed hundreds of thousands of cars and Ram trucks complete respective years of production. The Dodge Hemi V8 mightiness beryllium gone, but it's surely not forgotten. In fact, the Hemi V8 whitethorn not moreover beryllium gone aft all – we dream that's true.