What Made The Chevy Powerglide Transmission So Special?

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The Powerglide transmission utilized successful Chevrolets and immoderate other General Motors automobiles was introduced successful 1950. While it wasn't the first automatic transmission, its elemental creation made it an affordable action for a wider scope of car buyers.

First-generation Powerglide transmissions, produced until 1962, progressive cast-iron housings joined pinch bolts and gasketed joints. Overall it was heavy, had a imaginable for leaking fluids, and its two-speed cognition earned it nan nickname "slip-and-slide Powerglide." While it had 2 guardant gears, until 1953 it launched from a standstill successful apical gear, deriving its mechanical advantage from nan torque converter and only slipping into debased cogwheel to discuss steep grades.

It was nan Powerglide's 2nd generation, successful 1962, that made it truthful special — a astir indestructible transmission. Until it was discontinued successful 1973, replaced by nan Turbo-Hydramatic automatic, nan updated Powerglide featured an aluminum lawsuit that contributed to an wide weight 100 pounds lighter than nan original. Its robust building and elemental two-speed cognition earned it a estimation for durability among resistance racers, and pinch disposable aftermarket parts nan full transmission is rebuildable and stronger than ever.

Today's automakers person gone each successful connected automatic transmissions pinch progressively higher numbers of gears. One main quality betwixt nan two-speed Powerglide and nan 10-speed transmissions communal coming is the wide ratio versus adjacent cogwheel ratio variance betwixt shifts.

Two-speed Powerglide automatic transmissions don't person an overdrive gear. Instead, nan highest cogwheel ratio, 2nd gear, is 1-to-1 (1:1). While reasoning of ratios mightiness callback nan symptom galore of america knowledgeable successful algebra class, nan 1:1 ratio simply intends nan transmission's output shaft turns nan car's driveshaft 1 afloat gyration for each gyration turned by nan transmission's input shaft.

Powerglides intended for usage down six-cylinder engines of nan time were equipped pinch a 1.82:1 first-gear ratio, while eight-cylinder versions had a first-gear ratio of 1.76:1. The little cogwheel ratio of nan Powerglide's first cogwheel having a larger first number is counterintuitive. It intends that nan input shaft must move much to complete a gyration of nan output shaft: 1.82 aliases 1.76 revolutions, to beryllium exact. For comparison, nan first-gear ratio of GM's 10L80E automatic recovered successful immoderate last-gen Camaros is 4.70:1, pinch its 1.80:1 4th cogwheel being nan closest approximation of nan Powerglide's debased gear.

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Shifting problems are among the biggest complaints astir 10-speed automatic transmissions. One facet astatine nan guidelines of 10-speed transmission issues is nan complexity of power modules and soul components. The elemental operating parameters of nan two-speed Powerglide are its biggest strength. That's what drag-racing teams trust connected erstwhile building a car. Upgraded components disposable done aftermarket suppliers person erased immoderate of nan original Powerglide's shortcomings.

The mobility is really an antiquated two-speed transmission creation tin out-perform a modern 10-speed if some are operating astatine highest form. The reply lies successful powerfulness transportation and consistency. Modern 10-speed cars usage traction control or motorboat control to forestall instrumentality rotation nether acceleration. Neither strategy really provides much grip to nan tires. Instead, they some activity by reducing motor powerfulness or, successful immoderate cases, employing nan braking strategy to forestall instrumentality spin. And arsenic everyone knows, brakes only slow you down.

The Powerglide's lightweight rotating assembly and higher first cogwheel ratio, coupled pinch nan debased rear-axle ratio often recovered successful resistance cars, useful to supply consistent, usable powerfulness to nan rear tires disconnected nan line. In addition, pinch its 2 speeds, nan Powerglide only has to displacement 1 clip during each quarter-mile aliases eighth-mile pass. For a resistance car, particularly a bracket racer wherever consistency is key, less shifts correspond less opportunities for mistakes that could upset nan car and origin traction loss, resultin successful longer elapsed times.