You can buy the governor weight kits for your desired shift range, including Hemi and Max Wedge from A&A Transmission in Camby, Indiana.
Thanks for that information. Interesting!
Years ago, I found a comprehensive book on automatic transmissions at Half-Price Books. It gave a short overview of each automatic since the early 1940s and also went into their basic operation. ONE interesting thing was that the fastest shifts occur, especially 1-2 in a three-speed automatic, with the shift lever in "D" (listed as "breakaway" in the Chrysler service manual). Whereas most conventional wisdom indicated that doing a manual 1-2 shift was better as it gave the driver control of when the shift was initiated. After the book's explanation of how many fewer segments were in the "D" automatic 1-2 shift, compared to the manual 1-2 shift, it made sense and in a few really tight drag racing situations, might mean the difference between "WIN" or otherwise. Although all drag racers used the manual shift orientation, by observation.
After reading that, it seemed that the best situation would be to customize the weights in the governor to get the best balance of things so that the transmission operated as desired by itself, in "D". Which computer controls now seem to be doing for us. Customizing the governor weights (as
@Big_John mentioned) or buying the desired kits might really be the way to do things, especially at this "later date" of things.
Although I did not realize it initially when we bought our '66 Newport Town Sedan 383 2bbl car used when the '67s came out, was that Chrysler tended to set their WOT upshift points lower than optimum. But as that was our first V-8 automatic car, it had plenty of power for normal driving. "Competitive" but not nearly as "class-leading" as it might have been. It was not until I took the car to college in Lubbock,TX that I realized otherwise. At any red light, it was like a drag race when the light turned green. I was left in the dust of lesser vehicles, it seemed, so I realized that "more throttle" did not really help, but when I started to experiment with higher 1-2 shift points manually that I realized what was going on.
I discussed the issue with the old-line Chrysler service manager at our local dealer. He mentioned the kickdown rod adjustment as a way to increase the part-throttle shift points in "D". By that time, I'd already read many "horror stories" of mis-adjusted kickdown rods, so I was hesitant to experiment there. He then mentioned that he had done it on his '67 Newport with NO problems, so I got out the FSM and read up on that.
As I only needed a few more mph before the shift, I opted to first determine if the factory setting was correct. Which it was. Then I proceeded to add two more full turns to the linkage preload. That did the trick. Not a huge difference, but enough difference.
I had already been doing the manual part-throttle downshift to assist in freeway on-ramp acceleration, being able to do it without gaining any notice from passengers OR needing to use WOT to get a downshift. Knowing the engine's torque curve and such helped greatly, rather than just doing it one way all of the time.
When we got the '72 Newport Royal 400 2bbl car, as a part of the 3000 mile checkup, myself and the make ready tech went and did some fine-tuning on the linkage to get the PTK to happen easily, but not too easily. More acceleration with less throttle input, which I felt was a win-win situation.
When Federal emissions certifications changed from "PartsPerMillion" to "GramsPerMile", the lower "D" shift points seemed to become a bit lower, by observation. Enough so, to me, that the vehicles were doggy rather than perky and responsive. I test drove a mid-'80s Dodge D-150 5.2L V-8 (same power ratings as the Chevy 5.0L V-8, all spreadbore 4bbls) and the Dodge was very lazy, by comparison. I tried manually shifting it and it came to life, by comparison. Later, I drove a friend's '74 Ramcharger 5.2L V-8 and it was similar, very lazy. Then I got the '80 Newport 5.9L 2bbl and it was lack-luster . . . until I put a little bit more preload on the kickdown linkage. Then it felt normal, to me.
I realize, also, that with both the grams/mile and fuel economy testing, higher engine rpms are not desired in order to pass those tests. Which could have been the reason the kickdown road adjustments became harder to get to. From the earlier adjustment near the carburetor (threaded rod or slip 'n slide), as em
issios regulations tightened, it went to "under the cowl area" to "beside the torque converter area". With a special holding fixture tool to ensure the linkage was pulled as forward as it could be with the carb at hot base idle. I understand their reason for hiding it, but also knew some tweaking needed to be done in some cases.
The '72 Newport Royal was horrible, compared to the '66. It did the min-throttle 2-3 upshift at a speed that would effectively put engine rpm back to about 700rpm after the shift. So any acceleration which happened after that was "on the converter", unless more throttle was used, which would downshift the trans 3-2. Not good. I had determined that the min throttle 2-3 shift should put the engine at 1000rpm when done. Which was a tad higher on the torque curve than it was at 700rpm. More efficient acceleration, by observation. So that became my goal for those 2-3 upshifts. Which was about where I ended up with my experiments on the '66 Newport 383 2bbl car. So, with the 2.7 rear axle ratio, that meant 28mph and the 3.23 rear axle ratio, it was 25mph (my '70 Monaco Brougham 383 "N") . . . basically their "MPH/1000rpm" figures in high gear.
My fix, on the '80 Newport was a thin, black plastic wire tie. I placed it at the rear of the slot in the kickdown rod, on the bottom side of the slot. Effectively adding preload to the linkage in an easy fashion, but one which could be deleted with a cut by a diagonal cutter. The first one worked great, so as much as I wanted to further experiment, I felt that putting another one on the top of the slot might be too much, so I left it be. No transmission problems of any kind. No flaky activities, no colored-quickly fluid, no nothing. MY experiences, yours might vary, so proceed with caution!
These very small changes made the cars much more fun and enjoyable to drive in normal driving. More acceleration with less throttle input, "at the touch of the throttle". Discretion is the better part of valor, in these cases.
From what I read back in the earlier '70s, as Ford and GM both had part-throttle kickdowns on their transmissions, Chrysler resisted doing that. The article claimed that Chrysler had their reasons, BUT never explained what those reasons were. So it was probably market pressures more than anything else? Who knows how many "conquest sales" Chrysler lost because the cars did not feel as powerful as Mercurys or Oldsmobiles felt. although the horsepower and torque figures were very similar? BTAIM
ALL of these things apply only to low-to-part-throttle shifts, NOT WOT shift points, but are just one more way to better modulate those shifts so the transmission works better and makes the car feel better to drive, from my experiences.
Sorry for the length,
CBODY67
