Governor pressure is also directed to the 2-3 valve in preparation for that shift. I didn't have any in the car. Next is the tail shaft housing that contains the parking gear lever used to lock the governor-output shaft assembly in park and the output shaft support bearing snap ring. The rear clutch driving discs that are splined to the front annulus gear are free to spin, and the annulus gear is stationary. . For performance use, Brandes likes to see 0.
The springs and valves work together to modulate fluid pressure to time application of the bands and clutches. Note: Performance Automatic Chrysler transmissions do not include the driven gear for a cable driven speedometer or vehicle speed sensor. For 1966, the twin-cable shift and park control mechanism a holdover from the push-button operation was replaced by a solid shift control linkage consisting of a series of pushrods, rotating rods and levers. Moving to the top of the photo again, is the low-reverse lever assembly, its adjustment screw and lock nut, the reverse lever shaft and O-ring that the lever assembly pivots on and the rectangular strut that applies the low-reverse band. Bert and I were in the same Class of 1951.
However, most of these modifications for competition and heavy duty service sometimes made the transmission too severe for everyday use. Much like the later production A904 with a wide ratio gear a double wrap low-reverse band is used. The low-reverse drum B the band rides on had wear grooves, meaning the band was slipping, but it was saved by repolishing in a lathe. Here, the new parts have already been oil-dipped and trial-fitted hence the discoloration. The rear clutch is on in all forward gears. These and other driver errors can explode the over-running clutch unit also called the sprag and send shrapnel through the floor and through the headliner! This was a major boon for drivers, making the powertrain more responsive to sudden demands for more but not full-throttle power.
Improved High Gear Oil Supply The stator support is fed oil from a single quarter-inch hole pen points. Both 904 and 727 Torqueflites use the accumulator to give a cushioned drive breakaway only, depending on which side of the piston the spring is placed. This transmission differed from the A904 by having a re-enforced case and internals. Converter diameters and stall speeds will be discussed in the modification section. Previously, an automatic 3-2 downshift occurred only if the driver pushed the accelerator to the floor.
It was equipped with four direct friction plates. It is made up of the pump body, two rotors, and the reaction shaft support. Many thanks to David Frey, Vicki Milley, Debbie Hoflo, and a very special thank you to Tom Mallot for his photographic help. A double wrap band also called the Hemi or 440-6 pack band was used with the five clutch retainer drums in the maximum performance 727s. With the band released, the front clutch starts spinning.
Part 1: Overview, and what each part does This is part one of a three part paper. This is what applies the forward and rear bands inside the transmission. Your Legs Might Thank You. I've experimented with different types of products and they won't be named here. Part three give some of the techniques that can be used to troubleshoot Torqueflite irregularities that I've seen most often.
Depending on the original application and model year, strength and durability when used for high-performance work may vary. How do I purchase an eBook? The rear clutch is still rotating the annulus gear and the sun gear is stopped so no torque is transmitted to the rear planetary. Advantages to Torqueflite modification Advantage number one to Torqueflite modification is elimination of the 2-3 shift overlap which gives a crisp, efficient shift from second to third, prolonging the friction material life. The 1955 Packard had been the first car with a part-throttle kickdown. The front clutch is sealed to the reaction shaft by the two cast iron rings that direct oil from the pump to the inside of the front clutch. Apply the parking brake firmly with the engine at idle, then shift into each gear, momentarily ending in Neutral — not Park. Variants The toughest Torqueflite model — and the one most used by exotic automakers — was the A-727, which replaced the A-488 in 1962.
The only thing left to spin is the rear annulus gear which is splined to the output shaft. Installing the wider bushing requires changing to the later high-reverse drum and front stator support. In this case, the 727 core was a mid-level unit, representative of the majority of early 1970s big-block-style 727s, meaning it had several durability improvements over 1970-and-earlier units, without some of the economizing typical of some mid- to late-1970s versions. One might think it wise to use the Hemi-band with the standard 727 drums, but it will not work because of the width difference between the four and five clutch drums. Note the differences in the grooves and cross-hatch for each level of friction disc.
The 904 rear clutch is smaller but similar to the 727; and the front clutch hub-rear clutch retainer is in two separate pieces in the 727 but only one in the 904. Set the rear clutch much tighter, at 0. With the elimination of the rear pump the oil filter was designed with a single oil port. According to Chrysler, the TorqueFlites did not need periodic band adjustments or fluid changes, but periodic fluid checks are a good idea with these transmissions being as old as they are now. This is due to the converter not being fully charged in park. Reviewing the mechanics of this again will show that the planet pinions of both planetaries transfer the torque from the input shaft to the output shaft. Run what works best for you, but type F has proven itself in my book.
But choose wisely and be honest with your real-world goals. The Torqueflite is shifted automatically into second gear by a governor signal pushing the 1-2 shift valve over and allowing line pressure to be directed to the front servo-kickdown band assembly and to the accumulator. I will explain the pictures of the various units in the general order they are displayed and tell what functions the pieces have in the overall transmission operation in the following text. There are many types of kits made to improve Torqueflite and I'll give my recommendations on the ones I'm familiar with. McLeod Racing also now carries the full line of Raybestos performance friction materials.