History Dynaflow

1 history

1.1 original version
1.2 design rationale
1.3 performance
1.4 1953 redesign
1.5 1956 redesign
1.6 1958 redesign
1.7 termination
1.8 cadillac dynaflow
1.9 dynaflow in popular culture

history
original version

the dynaflow automatic transmission used in various forms in buick cars general motors corporation 1947 until 1963. transmission used five-element torque converter, 2 turbines , 2 stators, planetary gearset provided 2 forward speeds plus reverse. in normal driving, dynaflow started in high gear (direct drive), relying on converter s 2.1:1 torque multiplication accelerate vehicle. low gear, obtained via planetary gearset, manually engaged , held approximately 60 mph (97 km/h), improving acceleration.

the transmission incapable of automatic shifting, requiring driver move shift lever low drive cause upshift. buicks equipped dynaflow transmissions unique among american automobiles of time in driver or passengers not detect tell-tale interruption in acceleration resulted when other automatic transmissions of time shifted through gears. acceleration through dynaflow 1 smooth (if inefficient , slow) experience. because of slow acceleration dynaflow transmission nicknamed dynaslush.

the dynaflow inherently inefficient design due sole reliance on torque converter in normal driving. exacerbating situation dual stator arrangement, wasted more power simpler 3 element converters used other automatic transmissions, such chrysler s torqueflite. multiple stators increased turbulence in converter, when operating in coupling phase.

design rationale

during dynaflow era, many of buick’s unique engineering features ranked smoothness above other design , marketing objectives. dynaflow s non-shifting design demonstrably smoother rough shifting automatics available. moreover, buick’s torque tube live axle rear suspension design, incorporated rigid drive shaft 1 single universal joint ( u-joint ) @ front end of driveshaft, said amplify harshness of contemporary automatic shifting transmissions. dynaflow’s non-shifting design addressed characteristic of buick’s driveline. torque tube rear suspension simple design enabled buick use soft coil springs while competitors , corporate cousins used harsher, firmer leaf spring, hotchkiss drive rear suspension.

ironically, dynaflow’s smooth inefficient 5 element torque converter fed power through shiftless direct drive (plus 1 manually selectable low gear of 1.8:1) conceptual polar opposite hydra-matic used sister gm divisions oldsmobile, cadillac , pontiac. contemporary hydra-matic, world’s first large scale successful automatic transmission, used simple 2 element fluid coupling — more efficient torque converter provided no torque multiplication — feed power automatic 4 speed planetary gearbox compensated lacking torque converter including exceptionally low first gear of 4:1.

interestingly, dynaflow’s gearbox section derived chevrolet’s powerglide, 2 speed automatic planetary transmission incorporating conventional 3 element torque converter. 2 speed automatics 3 element torque converters common lower priced cars of day , in chrysler powerflite used in entire chrysler corporation lineup through 1956.

performance

dynaflow’s inefficiency earned buick reputation “gas hog” when compared heavy, powerful luxury cars of 50’s , 60 s. gas cheap , buicks upscale cars, gas hog reputation not serious sales deterrent.

manually downshifting direct drive “drive range” 1.8:1 “low range” enabled buick’s “torque monster” engines provide acceleration, though frequent “downshifting” took serious toll on transmission reliability. arguably, buick “family car” wouldn’t fare during teenage son’s “date night friday” outing.

engine rpm seemed more function of accelerator pedal position of actual road speed. flooring accelerator pedal cause engine speed flare (even though there no automatic downshift , no torque converter lockup disengage). car accelerate, rpm further climb, disproportionately smaller amount. more strangely, manually downshifting (see above) gas pedal floored not increase rpm in proportion 1.8:1 drop in gear ratio. dynaflow aural experience similar of continuously variable transmission (cvt) (though modern electronically controlled cvt s address throttle position dependent engine speed (and sound) characteristic artificially inserting stepwise ratio changes instead of continuous or constant rate change in order simulate more driver-satisfying genuine shifts).

1953 redesign

in 1953, buick redesigned dynaflow, calling twin turbine dynaflow . converter incorporated 2 turbines , planetary gear set, single stator. first turbine linked ring gear , second planets, gave 2.5:1 torque multiplication partly mechanical. resulted in better efficiency, @ highway speeds, , higher level of performance , no penalty regarding trademark smoothness. buick incorporated variable-pitch stator in 1955 greater flexibility. while these changes improved transmission s overall performance , efficiency, dynaflow still no match other designs utilized 3 element converters automatic shifting.

1956 redesign

in 1956 second stator designed torque converter @ outer diameter of turbines. provided @ stall ratio of 3.5:1 making performance comparable other automatic transmissions of time. design continued until end of production of twin turbine drive in 1963. however, triple turbine ended production in end of 1960 model year, leaving original dynaflow twin turbine automatic available in full-size buicks.

1958 redesign

a final version appeared in 1958 incorporating 3 turbines buick named flight pitch dynaflow . buick made transmission standard on top of line roadmaster 75 , limited models , optional on others. version further refined 1959 , renamed triple turbine offered option on models (buick dropped dynaflow name after 1958). unit similar twin turbine, bore operational differences, amongst them variable pitch stator increased converter s torque multiplication 3:1.

the stator element of torque converter has 2 blade positions, controlled driver via accelerator pedal offer passing gear , response @ speed heavy throttle application. in normal driving stator blades arranged @ cruise angle, improved efficiency , response @ light throttle. opening throttle changes angle of stator vanes hydraulically performance angle , permits converter achieve stall 1000 rpm higher in cruise . in situation oil redirected strike next-lowest drive turbine, lowers drive ratio, , allows engine speed flare speed output greatest. few identifying features: older twin turbine model fitted rear pump, meant vehicle push-started (considered desirable @ time).

also, twin turbine allow engagement of low gear 40 mph (64 km/h), , had shift quadrant read p-n-d-l-r. in contrast, triple turbine unit did not have rear pump, , not push started. allow engagement of low gear 45 mph (72 km/h), , had shift quadrant read p-r-n-d-g (where g stood grade retard ). grade retard feature not designed low or forward acceleration gear , meant used on long declines generate degree of engine braking. triple turbine cancelled after 1959 due technical problems , poor sales twin turbine being produced until 1963.

in late 1950s buick division of gm collaborated darby buick of sarasota, florida investigate potential marine uses of dynaflow transmission. test boat 21-foot correct craft. engine 364 cid buick 4 barrel rochester carburetor of nominal 300 gross hp. while boat attain speeds of 60 mph, considerable @ time, transmission suffered several problems. first, torque in reverse excessive, although have been alleviated different gear ratios. second, role of park in car necessitated stopped drivetrain. without locked-in-place tires of car, difficult put transmission equivalent of park.

termination

in 1964, dynaflow discontinued in favor of more efficient super turbine 300 two-speed , super turbine 400 three-speed transmissions, super turbine 400 being buick s trade name turbo-hydramatic. 1 feature of dynaflow, variable-pitch torque converter stator, colloquially switch-pitch , lived on in versions of turbo-hydramatic (super turbine 400) fitted full-size buicks, full-size oldsmobiles , cadillacs built 1964–1967, buick super turbine 300 , oldsmobile jetaway.

cadillac dynaflow

the 1950s cadillacs equipped hydramatic transmissions. in 1953 general motors hydramatic plant burned ground, leaving cadillac without source of transmissions. buick dynaflow transmissions hastily adapted cadillac mount points, , 19,000 1953 model 62 cadillacs, , 28,000 cadillacs of models, equipped dynaflow transmissions. several thousand 1953 oldsmobiles equipped dynaflow.

dynaflow in popular culture


dynaflow referred in episode of honeymooners called deciding vote (which first aired on december 10, 1955). in it, ed norton (art carney) tries explain troubles vacuum cleaner purchased wedding anniversary gift ralph kramden (jackie gleason) thus: armature sprocket causing interference; which, in turn, causes combustion line interfere flow , dynaflow. subtle sponsor plug/inside joke, buick sponsor of show in 1955–56 season.
ray charles second hit record, should have been me (1954), uses dynaflow sign of wealth , class in lyric, ...it should have been me, driving dynaflow! song written memphis curtis.
malvina reynolds song, day freeway froze , (1959) mentioned dynaflow in lyric, , little vw superbug winged dynaflow.
progressive bandleader stan kenton entitled recorded composition of dynaflow.
blues singer johnny shines wrote , performed dynaflow blues in 1960s, using automotive metaphors sexual performance
french canadian singer robert charlebois refers buick dynaflow in song dolorès 1968.
tony soprano references dynaflows while berating aged michele feech la manna in episode (season 5 episode 4) of sopranos.
in hyannis, massachusetts there street named dynaflow drive. passes car dealership
in movie rain man, automobile left tom cruise character has dynaflow transmission , picture of dynaflow badge shown in title credits.
the brian setzer orchestra s song gettin in mood contains line: , when start a-workin cruise dynaflow.
british music artist bill nelson s song, living in limousine , contained line 1 hand on steering wheel, m listening dynaflow
big joe maher s backing band called dynaflows.
michael nesmith of monkees recorded song called dynaflow 2006 solo album rays.
ian fleming refers ...slipping top through dynaflow gears in first chapter of second james bond novel live , let die.




^ cite error: named reference flory, jr. 2008 invoked never defined (see page).
^ auto editors of consumer guide (2007-11-26). howstuffworks introduction 1953 buick super . auto.howstuffworks.com. retrieved 2011-11-20. 
^ song lyrics day freeway froze, malvina reynolds . wku.edu. retrieved 21 october 2014. 
^ bill nelson – living in limousine (remix) / white sounds . discogs.com. retrieved 21 october 2014. 
^ big joe & dynaflows - biography - allmusic . allmusic. retrieved 21 october 2014.