I work on a lot of 63 to 65 Rivieras. The 63's with
the twin turbine trans feels great and is incredibly
smooth. The 65 Rivs with the VP 400 is also great to
drive, just a different feel, and the VP converter
definetly enhances performance.
I will say that many modern transmissions, especially
overdrive units, never know what gear to choose and
will sometimes shift at the wrong time.
But modern transmissions yield better fuel economy
than transmissions of yesteryear.
Marty
Thanks for those additional comments, Buicks Rule! They put many things into the correct perspective!
I heartily concur that much of what made cars of the '50s, '60s, '70s, and earlier were the unique "feel" each manufacturer's vehicles had from their competition. The way the transmissios worked, the starters sounded, the steering (and response thereof) felt, the engine sounds (!), and the particular ride characteristics were all "sensory inputs" that many of us still instinctively recognize and find joy in.
Back then, it was a decreasing "art" to know how to get the best performance and such from your vehicle and the way you used it. Knowing which buttons on the a/c to push or how to open the cowl vents just right, or setting the radio tone and speaker controls, for example. Even finding the best car wax was important.
But human beings being as they are, they had trouble moving from a Ford to a GM or to a Chrysler, with respect to how everything worked and where the controls were. When the federal law requiring standardized shift quadrant markings went into effect in 1965, it was the start of "sameness" in many respects--allegedly "better for the consumer". I suspect that brand loyalty was much greater back then than it might be now, so if you were a confirmed "Buick Owner", then you had no problems when the newer versions of your "old car" came out, but if a Ford owner decided he might check out the new Buicks, test drove one, and discovered that it was a world apart from his Ford, that he was used to--and he found the Buick just too different than his Ford--he might not venture off into Buick-dom, but as he was used to Fords, he might check out Mercurys instead.
Although GM controlled the car marketplace in the '50s and '60s (even to the notice of the federal anti-trust people), it was at its very best when every division was a unique operating entity and profit center, with much competition between the divisions for many things. Whether the accounting people were controlling the corporation or the engineering people were in control, the products were always setting the pace for Ford and GM in so many ways--at least in the mainstream market segments.
I've read that Fisher Body was requesting/demanding more common body panels on the various shared platforms from the divisional design people, even in the middle '60s. Similarly, there could have been more shared chassis items too, but there usually were not until the later '70s.
In those earlier times, each division had their own Chief Engineers that oversaw engine, transmission, chassis, and other aspects of THEIR division's vehicles. Sure, they had some idea of what their associates were doing in the other divisions and that they sometimes had to "share" things with them, but what rolled out of that division's assembly lines were Their Vehicles.
It was probably inevitable that certain functions would need to be combined to lean things down somewhat in the more modern arena of vehicle manufacturing. Common parts distribution network, foundries, stamping facilities, asssembly lines, engine plants, and tech support are places you might expect to be more standardized than not (just as Ford and Chrysler had been all along), but when the marketing and design functions became more common in later years, it seems that much of the things that made GM cars so great in prior times have somewhat evaporated. The differences in the carlines is much less distinct (other than trim and price) than in prior times. But at least if you buy the "right" Buick, it will have a Buick motor in it!
GM was trying many different things in the '50s and '60s, especially the HydraMatic Division. Some of the products came out good, but others didn't (as noted). I suspect that Buick held onto their ST300 as long as they did due to the smoothness factor (i.e., less gear changes) that would be closer to the traditional "Buick Feel" than the ST400 might be.
In the '50s-'70s (and earlier), each division usually had a local dealership that was not dualled with another GM franchise (much less some OTHER brand of vehicle). This was part of the GM heritage of divisional separation and helped better cater to their buyers. Then the "bigger and more is better" megadealer approach resulted in larger dealerships where many GM (and other) brands could be shopped at one time. Only thing was that a Cadillac or Olds or Buick customer typically would not set foot into a Chevrolet or Pontiac dealership for ANY reason, unless they were looking for a Chevy or GMC (usually dualled with Pontiac dealers) light duty pickup truck. And then the somewhat trendy "brand management" orientation did not produce the goods as it was supposed to have, by observation.
Now, the trend seems to be a blending of the two orientations, with a larger multi-line dealership having separate sales and service reception areas for each franchise, yet one combined parts/service facility.
Recent findings regarding the demise of Oldsmobile and retention of those customers in other GM carlines indicated that Olds customers usually went elsewhere than to other GM carlines. The old deal about "If they want a bench front seat, let them buy a Buick or Cadillac" just didn't seem to work out. It was stated that as many of the Olds dealers had picked up Kia franchises, as a second line, the loyal Olds owners decided to stay with their established dealership than to remain loyal to GM, converting to Kias when they needed a newer vehicle. Where they end up at their next trade cycle might be interesting to watch. Sometimes, it seems that new "whiz bang marketing" and trying to force buyers to accept what you want to build just does not "meet or exceed expectations" of sales successes in an open marketplace.
Regardless of what brand of vehicle you want to talk about, they typically have their best years when they produce something exciting and interesting to the car buying public, especially the "non-appliance" segment. Perhaps the "next" model cycles will produce the USA designed/built vehicles that will again rekindle some of the excitement of earlier times? What sold lots of Buicks in the '50s can sell them again in the 21st Century--Style, Power, Distinctivness, Desireability, Luxury, Affordable Price, and extended-term GMAC financing ("financing" is kind of a moot point at the present time.).
Enjoy!
NTX5467
This discussion on the Flight Pitch Dynaflow is interesting. The 1950's were not just the beginning of the horsepower race, but of the "build a better automatic" time.
First, I do believe in the original 4 speed hydra-matic, in that it was designed in the 30's and had both performance and durability in mind. Those transmissions were just about bomb proof.
But we are talking about Buick and Chevy transmissions, primarily shiftless types.
My father ordered a new 1959 Chevy with a 283 and Turboglide. The reasoning behind the Turboglide choice was a wonderful magazine by the name of Popular Science. They recommended the transmission and he went along with their advice. Yes it was smooth, but when the torque converter died after 2900 miles, there were reliability issues. The dealer replaced the converter and from then on it seemed to be pretty reliable. But there were obvious performance limitations.
The Turboglide stator only changed with the accelerator floored. Therefore performance was very limited. I think the Buick Flight Pitch had an infinitely variable stator, and in theory should be better. But to me there is a very distinct missing ingredient in both of the trannys, a way of getting a gear reduction to pass more efficiently.
This is something that GM never thought of and may have made the triple turbine trannys more desireable.
I currently am looking for a reasonably good 58 roadmaster with one that has FP tranny. I have a FP tranny that I am thinking of trying to rework to provide a way of getting back to intermediate gear by way of sensing vacuum, car speed, and accelerator position. The car speed would use the rear pump pressure to provide feedback like a governor does on a shift type tranny. Vacuum sensing would be provided via vacuum modulator, and the accelerator position is already there.
I would think some creative valve body reworking would provide clutch actuation, but the triple turbine converter is another thing. Still thinking about that one.
In your performance comparison questions, motor trend did a side by side performance of two 1958 Buick Supers, one with FP and the other with VP. Their results were pretty clear, the VP did better on acceleration than the FP, and it seemed to "slip" less than the FP. The issue in the test was that the VP was started in LOW and then upshifted manually. This I believe is unfair.
If you take a Turboglide and Powerglide comparison using a 283 engine, the Turboglide has it all over the PG from the start, but eventually cannot hold on due to it's progressive ratio changes. So the theory is somewhat correct, but not fully. Being able to select a reduction gear when needed is the missing ingredient in my opinion.
Lastly I find it hard to believe that GM spent 86 Million on development of this transmission, especially in the 50's.
<img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" />
There was a "difference" in the TurboGlide and the DynaFlow, though, and that "difference" was that "GR" (Grade Retard) in the TurboGlide was NOT considered a "low gear" but only for keeping vehicle speed under control on long downhill roadways (i.e., in the mountains). In some of the HD truck automatics, I believe they also had "GR" situations in their shift quadrants (which was noted in Chevy print advertising for their cars with TurboGlide) . I believe that if you read a Chevy owners manual during the TurboGlide years, it will state that "GR" is not to be used for normal driving situations, unlike the DynaFlow's "Low" range.
One of the "driving forces" behind the "more speeds" in modern automatics is to keep the torque converter in a more "locked-up" (but not with the torque converter clutch in "lockup" mode) condition during more driving situations, which should be more fuel efficient. Otherwise, torque converter "slip" (the normal amount rather than otherwise) would make up the difference plus take more throttle input to make that happen.
The other situation is that a Flight Pitch Triple Turbine DynaFlow torque converter (from the pictures) appears to be "thicker" than the normal torque converter, with a related "build length" increase in the transmission assembly (front to back). Adding another planetary for a "kickdown" gear addition would further add length to the unit, I suspect. For example, look at how much longer a GM 4L80E automatic is compared to a 3L80 (THM400) automatic, not to mention the added weight.
Also, considering how "advanced" Buick was probably trying to make the 3T DynaFlow appear, if they had had a kickdown position that utilized a planetary gearset to make that happen, it might have been interpreted as a "two-speed automatic with a fancy torque converter" rather than the technological advance marvel it was supposed to be. Buicks were noted for their driving smooooottthhhhhneeessssss, which (at that time) meant "no gear changes" in the transmission in "D".
The first few years of TurboGlides were known for their reliability (means "trouble-prone" and "nobody knows or wants to work on them") issues, but after those first years, they got much better. My uncle bought a new '61 Impala 4-dr ht with a 283 and TurboGlide. When he bought it, he was stationed in the Air Force in IL, so the TurboGlide might have been easier to drive in the snow . . . or the dealer ordered something that was a nice car and "drives as smoooth as a Buick"? I remember that he had very little transmission trouble with it, other than a few fluid changes and a "downshift" linkage adjustment (once) before he traded it for a new '67 Pontiac Executive 4-dr sedan.
From what an old-line used car dealer mentioned one time, some of the car rental companies back then (i.e., Hertz) bought some '58 Chevies with TurboGlides in them. As they had a good bit of trouble with them, they "turned" them pretty quickly rather than fix them. He said he bought them cheap and helped a mechanic convert them to PowerGlides before he resold them--alluding that many of the earlier TurboGlide cars had PowerGlides put in them when the TGs broke.
My machine shop operative also mentioned, once, that the first year's TG case was too weak. He had a friend that bought a new '58 Impala. The first time he went through a dip too fast, it bottomed out and the trans case cracked. Whoops! but then some of the Buick dealer mechanics had their own "pet" names for the DynaFlows back then too.
Also remember that in those earlier times, everything was generally done "cut and try" rather than use computer simulations and such. More money and time consumption, for sure, not to mention tooling expenses (probably a good chunk of those millions of $$$$$ quoted in the ads!).
It might be interesting to find two similar cars and do a "drive test" with them, one with the normal DynaFlow and the other with the 3TFP DynaFlow. Checking "feel", acceleration (real and perceived), and a fuel economy check (noting differences in each car from the other, in the test comparison). Supplementing that article/comparison with some of the archived information on what the "benefits" of the 3TFP DynaFlow were (in engineering orientations) might be neat, too.
Just some thoughts,
NTX5467
Enjoy!
NTX5467
NTX5467
You are correct that the VP Dynaflow has a "real" low gear, whereas the Turboglide has the Grade Retard position (or HR hill retarder in 1957) that is only used to slow the car down on grades or for push starting the car. In my previous post I had mentioned that the Turboglide had a two position stator in the converter, whereas the FLIGHT PITCH converter has an infinitely variable stator. This is what I was refering to as far as differences between TURBOGLIDE AND FLIGHT PITCH DYNAFLOW. The variable pitch dynaflow is a totally different transmission, with only some similarities in having more than one turbine in the converter.
I have driven my father's Chevy with the Turboglide against another Chevy with a Powerglide and the results where somewhat predictable. The Turboglide has a first gear reduction, which works with the first turbine, therefore the lower gear ratio makes it quicker from the start, but after the second and third turbines become active the Powerglide is still in low gear and therefore makes the Powerglide strong in the 25 to 60 Mph ranges. After that it is a moot point.
I would think the same would be true with the FLIGHT PITCH VS. VARIABLE PITCH. That of course is if you are holding the Variable pitch in Low range till 50 mph or so. If you start in D, then I would think the FLIGHT PITCH would have the edge.
I drove a 58 special with VARIABLE PITCH and it was slow as molasses in D from a standing start. But with a Low gear start it wasn't too bad.
The reasoning behind the kickdown feature is this: When you needed to pass someone with a shiftless transmission such as Turboglide or Flight Pitch, the only feature you have to rely on is the stator angle, which doesn't do much when you need passing ability. All shifting transmissions will downshift and provide much more ability than just a stator angle change.
As far as modifications to my FLIGHT PITCH, my thoughts were to rework the valve body to apply the second gear planetary clutch (already there) when the vacuum was low, the accelerator was floored, and the roadspeed was in the 30 to 50 Mph range. The second gear turbine is the key. Somehow the third gear turbine would have to be inactive during the forced downshift to second. I have the FP manual, so I should be able to figure out the paths to do what I want.
The funny thing about that transmission is that when you are in GR position, the tailshaft is supposedly locked to the first planetary gearset and back drives the first turbine, which in turn tries to drive the engine, along with heating up the rest of the converter. If you try to drive in GR the car will move but will only go about 8 Mph at best. Maybe you can explain why the transmission's GR position doesn't work as a low gear.
Thanks for the reply
<img src="http://forums.aaca.org/images/graemlins/smirk.gif" alt="" />
Back in the later 1970s, when transmission oil temp gauges were first (seemingly) being used on the heavier camper/tow pickups (aftermarket gauges with a magnetic pickup for the automatic transmission's oil pan), our then-Service Manager took one out for a check out. We all knew that a torque converter would slip some when power was applied and the vehicle was not moving as fast as the engine wanted it to go. So, he got it up to operating temperature, then stopped on the side of the road. Then with the foot brake fully applied, the trans in "D", he started torqueing into the engine (ala drag strip starting procedure) some. The trans temp raised a little. Then he did a WOT acceleration, still not much temp increase. Then, with some road speed, he pulled it into "2" and did an engine braking slow-down. The temp increased a good bit.
When he was telling us this, his little brother (who used to do parts for a major construction company) agreed that when the converter was in "overrun", it built far more heat than when it was under power or "pulling". In the overrun mode, the oil in the converter is running into itself, basically, which slows things down and lets less heat dissipate through the coolers--especially for an extended period of time.
As for the other issue you mentioned, only automatic transmissions with a "rear pump" would allow the vehicle to be push-started "in a forward gear". Seems like the drill was to get the "pushed" car up to about 20+mph, let the "pusher" car back off, and then the first car was shifted into "D" and the engine was supposed to start and then it could drive on its own . . . as long as the engine was running (with the dead/low battery). When the rear pump was deleted in the earlier 1960s, you had to get a set of jumper cables.
Perhaps, with some "hidden electronics", you could do the actuations electrically and use some current production shift solenoids (or similar) rather than linkage? I understand that if you know what fluid needs to go where, there are some "hidden possibilities" for "extra gears" in many later model automatics . . . and probably in some of the earlier ones too.
Enjoy!
NTX5467
Hi, I have imported four 58 Buicks into the UK & owned & for me the standard dynaflow was always a more responsive & more efficient transmission than the Flight Pitch.................. which is smooth but supremely inefficient in the three I have had.
Was the takeoff from "standing start" better with the "triple turbine"? What about passing acceleration?
Thanks,
Marty
In my opinion the standard dynaflow was much better with both of your points than the triple................... I just found the standard dynaflow more responsive & less inefficient.Originally Posted by MartyWorld
Was there any advantage to the flight pitch trans? A lot of money and complexity it seems to provide no real benefit.
Any other opinions?
Marty
The OTHER thing to consider about the 3T Dynaflow was that in that era, people generally bought things which others could see rather than things "under the skin". Therefore, they would have been more inclined to purchase two-tone paint or whitewall tires than a "fancier" automatic transmission (when the "normal" DynaFlow was considered to work well enough as it was), unless the fancier transmission came as part of the model's standard equipment.
It might be that one reason the normal DF is considered "more efficient" is that it loads the motor more during acceleration more than the 3T would, due to the lack of greater stator angle variation in the DF's innards. A different exhaust sound, I suspect, with small throttle movements. One of those situations where throttle "feel" and sensory input might not really equate to faster actual acceleration?
Having not driven a 3T myself, I did spend a weekend with a Nissan Altima and the CVT a while back. It did have a different feel and the rpms did sometimes not fit what I felt they should be (too high) during mild acceleration and light throttle input.
Other than the peer pressure of "You spent how much for an automatic transmission upgrade when the normal DynaFlow was just fine???" situation, I suspect that in normal driving there would be little return on the investment, but in larger throttle input situations, where the additional torque multiplication might help, only THEN might the extra money for the 3T have been worth it.
But then too, when a new car prospect gets into a car that drives "differently" than what they are used to, or might require a little more finesse to get the extra performance from it, there can be a negative orientation toward "the change" as "it's different than what the customer is used to". So, when you punch the throttle and hear more engine rpm than you might perceive you feel from "thrust", although the 3T might actually be quicker, unless you "feel it" or hear the exhaust sound like the engine's "working", it's "wasted money" . . . by observation.
Just some thoughts,
NTX5467
Perhaps Buick should have considered using the "two position" stator instead of the "infinitely variable pitch" stator on the triple turbine transmission.
If Buick kept the design longer than 58 and 59, more development would have led to a more efficient design.
Marty
Flight-pitch (1958) and Triple-Turbine (1959) used the same three turbine ratios, 1st-2.86 / 2nd-1.54 / 3rd 1-1. All '58 models came w/3.23 real axles - '59 had 2.73. Also '58 300 hp vs. '59 325, so any comparison to Variable Pitch Twin-Turbine which uses 1.6 ratio 1st turbine and 1-1 direct, should be made with cars using same rear axle and engine. Clearly, the three turbine units blast off the line better and '58 models can get a little rubber--not so w/any twin turbine starting in drive. Like comparing a second gear start to first. Most road test acceleration specs. for Twin-Turbine use Lo start which multiplies another planatary unit in the gear box 1.82 X 1.6 plus stator and shift to drive at 50 MPH.
Triple turbines had a 3200 rpm stall - twin 3100 rpm. Stator channels returning oil to inner blades of pump at 51 degree maximum high angle utilizing regenerative force to drive pump much faster than engine torque alone, or most fixed stators of the day (T-Birds and Lincolns about 1950 rpm stall) w/30 degree angle. Flight-pitch stator low angle (20 degree) began to advance at 1/2 throttle and gradually increased pitch as pedal went further down--full advance when floored. This freed the engine RPM so the reduction turbines could get a "bite" from the whirling mass of oil being projected. The key was differential in speed of the pump and reduction turbine to obtain torque multiplication from one or both of the geared turbines, depending upon vehicle speed and throttle position. Twin-turbine stayed in very low stator angle at all times other than WOT, so RPM remained lower most of the time, so did performance, but again apples to apples to actually realize that.
Inside three turbine converter: Pump projects a rotating cylinder of oil out-wards, due to centrifugal force, against the turbines--the first having slightly angled blades and 2.86 ratio, absorbs most of the energy in the oil at start up. As acceleration proceeds, first turbine turning almost three times drive-shaft speed spins closer to pump speed and more and more 'out of the way' of the pump, providing less and less resistance. At this point, some of the forward projection of oil from the pump makes its way past the blades of the first turbine uninterupted, and a small percentage of the total oil flow begins to strike the blades of the second turbine. Torque is now split between 2.86 and 1.54 turbine ratios and gradually, as vehicle speed increases, second turbine absorbs more energy and the first less, until the first turbine spins slightly faster than the pump. Then the rear ring gear over-runs or freewheels. This process is repeated from second to third turbines, except highly angled blades of second turbine allow it to freewheel (release front sun gear) at considerably higher rpm than engine driven pump speed and of course higher vehicle speed due to 1.54 front planetary ratio.
Ultimate smoothness at all times and normal performance acceleration requirements presented no real deficiency, except--because three turbines shared torque, greater rpm was needed to experience the same acceleration rate of a 3-speed sequenced-geared conventional torque converter, Ford-Chrysler type. WOT starts 0-45 MPH are strong, but when turbine two gave way to three at higher speeds (above 50), geared torque multiplication fades out to zero a little too early, losing top 1100 engine RPM-hp. 50-70 passing times were therefore longer than a transmission that could downshift to isolated second gear, which allows engine to concentrate full RPM hp on that reduction gear only. Only way around sharing torque between turbines two and three at full throttle would be to release the third turbine direct (neutral) clutch. Unfortunately the spokes on turbine two would snap when all 445 lbs of Buick 401 torque were unleashed at once during passing. Too bad, otherwise what a brilliant idea! Buick was first to advance fluid coupling to torque-converter using regenerative stators, R&D by Invicta in the '30's.
Last edited by B/W; December 27th, 2009 at 10:10. Reason: spelling
Dyna-flow was first to use torque converter in 1948 models over fluid couplings which had origin in marine use in Germany in 1890's. Two piece fluid coupling called "Fluid Flywheel" used by Daimler in England in 1931. First 5-element torque converter developed by Buick's Invicta division had two piece stator and two pumps (smaller angled blades of secondary pump within primary pump w/1-way roller clutch freewheeled out of the way during acceleration but provided more solid coupling at cruise). There was only one turbine and 2 stators provided 2.25 max at WOT starts w/straight 8 and 1850 RPM. Gearbox like Power-glide, but Drive was direct-no reduction unless manual shift to Lo, a must for hill climbing or fast starts.
1953 added reduction turbine with narrow band of slightly angled blades geared to second turbine within converter at 1.6 reduction. Stator angle was reduced, so were RPMs to 1600 but acceleration improved due to 1.6 ratio geared turbine torque multiplication. Normal Drive range now provided similar start up feel to earlier model with out having to manually shift from Lo to Drive. Turbine one at 1.6 reduction started the car out in something similar to second gear and gradually phased out as speed increased. Lo multiplied 1.6 X 1.82 or 2.91 overall gear ration plus stator, Centuries and Roadmasters became barn burners.
1955 added Switch-Pitch stator to Twin-Turbine and WOT acceleration in Drive improved again. In 1956 the first turbine blades were longer and highly angled for greater extension of effectiveness. High curvature of the blades meant greater absorption of oil projection at higher speeds and allowed the 1.6 reduction to be utilized at even higher freewheel RPMs than pump, because as first turbine caught up fully to pump and then "passed it", turbine RPM exceeded pump and tips of elongated blades still absorbed some torque. The high angle of these blades necessitated the use of a secondary stator between turbine one and two to prevent force of oil that was projected backward from retarding second (direct) turbine at start up. This stator freewheeled at 30 MPH-WOT. Unit remained basically unchanged through 1963, provided max. torque 3.5 at stall in drive.
1957 Chevrolet's triple turbine Turbo-glide mid-year. Ratios 2.67 - 1.6 - 1 -1. dual position stator 3.8 max lo-angle 4.2 max hi-angle. Early cone clutches failed, improved in 1958-59 w/multi-plates and 5 spoke second turbine, 1961 last year.
1958 introduced Flight-pitch 4.5 max with triple turbines and was re-named as such in 1959 (bigger motor produced 4.75 max), then dropped (operation described in previous post of same). Obviously, I am very fond of these Dyna- flows and Turbo-glides and think improvements could have continued - what with the quick advances of the single then twin-turbine Dyna-flow, apply that to the Triple Turbine and within a few years it may have been reliable and efficient. Unfortunately GM did not ask me then as I was 8 years old, and probably figured since I couldn't buy a car my opinion didn't matter. However, I did know how they worked by the time I was twelve, but they were already obsolete. What a loss! Just my opinion.
Last edited by B/W; December 27th, 2009 at 14:20. Reason: grammer
B/W, thanks for that detailed description of the operational dynamics of the various DynaFlows!
Although Chevrolet offered the TurboGlide as an upgrade from PowerGlide, Buick was somewhat "stuck" with their signature DynaFlow automatic. From what older used car dealers have mentioned long ago, almost every TurboGlide vehicle they bought (with a bad trans) was replaced with a PowerGlide from the salvage yard before they resold the car.
I had an uncle that bought a new '61 Impala with a TurboGlide. At the time, they were in Illinois with the Air Force, so it might have been that the TurboGlide might have been better in winter driving conditions? The car was a 283 V-8 and it ran and performed "as expected", just no 1-2 shift as the car gained speed. No issues with the trans before they traded the car for a '67 Pontiac Catalina, just normal fluid changes every so often.
As great a the DynaFlows might have been, it's obvious that they did not have the torque capacity to handle the newer and more torque-laden V-8s of the then-future, nor the projected 1962 Wildcat Turbocharged 401 V-8 model. By the early 1960s, it was obvious that as cars became quieter and smooother, the greater efficiency of single-element torque converter step-gear transmissions was "the future" of automatic transmissions in the USA. Refinements provided nearly imperceptible shifts in normal driving, with the latest electronics and electronic controls providing "shift feel by watching the tachometer".
Thanks, again, for the great explanation and insights!
NTX5467
By 1961 TurboGlide lost the cone clutches, had six pinion planetary instead of three and the second turbine had five 1"spokes instead of three 3/4", which usually broke within 20,000 miles, plus several technical improvements, so the bugs were out. They weren't cheap to build and three element converters are smaller and lighter, plus sequence gearing uses full engine power. Shared turbine torque that is actually gradually transfered from high reduction turbines to lower reduction ones during acceleration is smoother, but costly in fuel and some wasted power. They were luxury drive systems suitable for Cadillacs and I just love the cush! Dynaflow does get credit for the stator (torque multiplier) used in all of today's converters and there are some industrial twin-turbine drives systems still built for stationary use, so wasn't all for not!
Enjoy a stage of engineering development if you have one!
Last edited by B/W; December 27th, 2009 at 17:58. Reason: spelling
B/W, thank you for your additional comments on this topic.
As the owner of a '59 Electra with Triple Turbine, I enjoy the unique aspects of the transmission, and am pleased with the overall performance.
Last summer, we drove seven 1959 Buicks together from Seattle to Colorado Springs, and our cars consisted of three LeSabres with Twin Turbines and the 364-cid 2-barrels; an Invicta with 401 and Twin Turbine; two Electras with 401, dual exhausts, and Twin Turbine; and my Electra with 401, dual exhausts, and Triple Turbine. We drove mostly together as a group at highway speeds, and usually re-fueled our cars at the same stops. While I wish we had been more deliberate about checking gas mileage, my Triple Turbine Electra seemed to be at least as fuel efficient as the Twin Turbine cars. At one stop, I noted that it had consumed less fuel than the 364-cid 2-barrel LeSabres with Twin Turbine, but the cars were all remarkably consistent in terms of fuel consumption.
Brian Laurance, BCA #5168
1959 Buick Electra 4-door hardtop
1971 Buick Centurion Formal Coupe
1989 Buick LeSabre Limited Coupe
1990 Buick LeSabre Limited Coupe
Thanks for the additional information, B/W!
NTX5467
B/W, thanks for the incredible info.
If the stator was in high angle due to WOT, wouldn't the second turbine carry more of the load beyond 50 mph?
Marty
Yes, that was the idea. Second turbine would turn @ 1-1/2 times drive-shaft speed until it freewheeled. If the engine turned 1000 RPM per 25 mph, for example at cruise, (1958-3.23 rear axle) then it took 1500 RPM or more to engage the second turbine at 25. 3200 RPM stall WOT increased to 3800 at 65 mph, then you can draw some lines on a graph and see exactly where the second turbine fully reaches pump speed. Length and angle of second turbine blades allows it to still share torque with third turbine beyond pump speed, how far beyond has never actually been published in any SAE reports I am aware of, but others may have more info. That's what these sites are good for.
All three turbines receive forward energy form the pump as car speed increases during acceleration. Reduction turbines reach pump speed quicker than direct turbine-thereby sharing torque less and less until fully phased out-which will always be below 4000 rpm. Unfortunately, this forfeits last 1000 rpm up to engines full capacity of 5000 rpm. Sequenced geared transmissions do not have this limitation, which showed up most noticeably during high speed passing.
Last edited by B/W; January 1st, 2010 at 01:00.
Thanks for all the info. I have been intrigued by Dynaflow ever since being a passsenger in a 1963 Invicta station wagon back in 1973. My recollection is that the driver said it was a 1964 but that cannot be true, unless it was a late 1963 registered as a 64. I was truly astounded that the transmission was designed to run entirely in high gear.
My question is about behavior/driver impressions of the 3T regarding engine braking in "GR". How does the engine braking compare to a 2-speed or 3-speed automatic on a 10% downgrade, or similar quantifiable situation?
Another question (urban myth category?) Someone once told me that Dynaflow could be shifted into Reverse while moving forward at highway speeds and the car would slow down smoothly without damage to the transmission. Sounds crazy to me now, but I was young and impressionable then....
In case anyone wonders, I have never owned a Buick, but may someday. I did own an interesting car with a CVT. It was a DAF, built in Holland. I called it "Dutch Dynaflow" (hope that doesn't offend anyone here).
Okay enough of me blabbing for now.
I don't know that much about the turbine flows but I think it would be destruction time to shift into reverse at highway speed. My 56 manual says that in the twin turbine, reverse band actually locks the reverse drum causing the gears in the pinion to reverse direction. The reverse band is like an external drum brake.
If someone actually did this then they probably broke the reverse strut that applies the band and that indeed would allow the car to continue forward motion. But backing would be quite a chore thereafter as you'd need several strong people to push the car manually.
John C. De Fiore BCA # 3757
56 Super 56R: acquired September 1974
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Twin-Turbine compound planetary gearbox 1.82-1 Lo gear ratio produces downhill braking similar to Power-glide or other 2 speed selective shifting automatics in Lo up to @60 mph.
Triple-Turbine isolates 1st turbine 2.86-1 ratio in "G" grade-retard range. Not useful above 45 mph (over-rev) and braking is fierce! Almost like 1st gear in a conventional three-speed.
Reverse in the Twin-turbine engages the rear band, locking planetary drum, reversing direction of planet pinion carrier. Several things could brake if reverse is engaged while driving forward besides the band strut, which could crack the case. If sufficient speed were involved, planet pinion shafts (weakest link) in both 1st turbine torque converter planetary and gearbox compound planetary pinion shafts/carrier assembly could all shatter, leaving the car without forward or reverse and lots of metal in the valve body!
I'd follow the manual, which requires full stop before moving shift lever to change direction.
One scenario that could be equated to shifting into reverse when the car is going forward is this: Icy road, driver hits brakes and stops the rear wheels, then shifts to reverse, then hits the gas pedal while releasing the brake pedal. The rear wheels would then turn in reverse, of course till the wheels hit solid ground, then goodbye Dynaflow!
My father had Turboglide in a 59 Chevy with 283 and used Grade while descending mountain roads. It shifted quite smoothly, but it had a vacuum modulator which helped with the engagement of Grade. The Flight pitch and 3T do not have vacuum modulator, instead they use the throttle rod (which also controls the stator angle) to regulator apply pressures for Grade range.
1957 Turboglide used three cones and one multi-plate/disk clutch. Use of vacuum modulator was needed due to harsher engagement of cones. They have great static holding power but little heat absorbing lining so they burned up if engaged in Drive while moving back-wards and vice-versa for reverse.
1958 Turboglide had two cones and two multi-plates - 1959-1961 dropped the cones and vacuum modulator retained all five years.
1958 Flightpitch had all multi-plates (four) and no cones. ''Stack'' type plate clutches have many times more lining than cones (depending on number of plates 3-5) but the Turboglide Grade retarder didn't have enough to hold full throttle torque and would self-destruct if used too many times as a "passing gear". This same problem plagued the Flightpitch and Triple Turbine but if driven as instructed in Drive only, both Turboglide and Triple Turbine from 1959 on were much more reliable.
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