Turbo350 w/shift kit slamming 2nd gear

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NickTransmissions

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I think you mean 84. IIRC, 82 was the first year for the 700r4. The 82-84's were really bad. GM even offered some people to convert back to the Th350 when people got sick and tired of putting their new truck in the shop for transmission warranty work. Though the valve bodies in the 82 through 84 are sought after.
Yep, avoid 82-E84 700R4s or convert them to L84-87 standard (30-spline shaft, newer design "152" drum and 29 element sprag. Top it all off with a factory 10-vane rotor/slide kit and it's good to go for most applications.
 

NickTransmissions

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I think you mean 84. IIRC, 82 was the first year for the 700r4. The 82-84's were really bad. GM even offered some people to convert back to the Th350 when people got sick and tired of putting their new truck in the shop for transmission warranty work.

I have to admit, Ford did much better than Dodge. At least Ford tried and eventually did made a NEW 4 speed auto. Dodge's idea of a 4 speed OD auto, was they just took the same 904 and 727 which is their versions of the Th350/C4 and Th400/C6, they used the same transmission, put an electronic OD unit on the back, gave it a different model and there you go. BOOM, 4 speed OD. Which, I have to say, there are advantages to that, and I had thought at one time I'd like to have gotten one those Dodge Units and see if I couldn't somehow adapt it to a Th350 or Th400 like a cheap gear vendor. I never did get to play with one since I quit building by then. I did very few Dodge and Ford transmissions, mine were mostly all GM RWD. I think a total of 3 transaxles is about all I've done, 2 GM and a damn, oohhh crud what was that thing in the Plymouth Reliant?
Fun Fact: Chrysler was nearly bankrupt for large portions of the 80s and early 90s and didn't get around to developing overdrive transmissions until nearly a decade after GM and Ford. When they did, they leveraged their A345 design from the mid-70s, which was a an optional extension assembly bolted to the rear of the 727s in place of the standard extension housing. This specialized assembly provided some of the trucks thusly equipped with a "granny" gear in front of "first" gear, basically creating a 4 speed unit that use a 3.45 granny gear, then the standard 1st gear of 2.45-to-1, then 2nd gear of 1.45 then direct (1 to 1).

The 42RH/46RH took that same concept but instead of granny gear, they came with an overdrive gear set, enabling a .69 to 1 ratio that was in production until 2007 then replaced starting in 08 with the introduction of the 6 speed 68RFEs...
 

AuroraGirl

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Fun Fact: Chrysler was nearly bankrupt for large portions of the 80s and early 90s and didn't get around to developing overdrive transmissions until nearly a decade after GM and Ford. When they did, they leveraged their A345 design from the mid-70s, which was a an optional extension assembly bolted to the rear of the 727s in place of the standard extension housing. This specialized assembly provided some of the trucks thusly equipped with a "granny" gear in front of "first" gear, basically creating a 4 speed unit that use a 3.45 granny gear, then the standard 1st gear of 2.45-to-1, then 2nd gear of 1.45 then direct (1 to 1).

The 42RH/46RH took that same concept but instead of granny gear, they came with an overdrive gear set, enabling a .69 to 1 ratio that was in production until 2007 then replaced starting in 08 with the introduction of the 6 speed 68RFEs...
chrysler sucks. cant even call it part of the big 3 anymore,. althogh they all love to outsource labor , at lesst ford and GM are *still* american car companies. hows fca.. i mean.. stellantis again?
 

HotRodPC

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Fun Fact: Chrysler was nearly bankrupt for large portions of the 80s and early 90s and didn't get around to developing overdrive transmissions until nearly a decade after GM and Ford. When they did, they leveraged their A345 design from the mid-70s, which was a an optional extension assembly bolted to the rear of the 727s in place of the standard extension housing. This specialized assembly provided some of the trucks thusly equipped with a "granny" gear in front of "first" gear, basically creating a 4 speed unit that use a 3.45 granny gear, then the standard 1st gear of 2.45-to-1, then 2nd gear of 1.45 then direct (1 to 1).

The 42RH/46RH took that same concept but instead of granny gear, they came with an overdrive gear set, enabling a .69 to 1 ratio that was in production until 2007 then replaced starting in 08 with the introduction of the 6 speed 68RFEs...
Yep, I member those days. Lee Iacocca, Former Ford President took over for Chysler and saved their azzes. While he kept them afloat, I think it was the 94 New Generation pick up that launched them forward back into black ink.
 

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Yep, I member those days. Lee Iacocca, Former Ford President took over for Chysler and saved their azzes. While he kept them afloat, I think it was the 94 New Generation pick up that launched them forward back into black ink.
chrysler frankly should be very grateful, they nearly died and then died so many times lol.. Like when they couldnt keep their m1 tank contract anymore in the 70s
 

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chrysler frankly should be very grateful, they nearly died and then died so many times lol.. Like when they couldnt keep their m1 tank contract anymore in the 70s

Read Lee Iacocca biography, he discusses how painful it was to sell the tank contract.

I’m paraphrasing because it’s been several years since I read the book, but he explains that by selling the contract for the tanks, he was giving up a guaranteed 600 million in profit, in a market that by law the Japanese weren’t able to compete with.

If you haven’t read his biography, it’s very interesting. It’s also very depressing, because a lot of what he predicted 40 years ago happened.

As someone who has studied the automotive history, it seems the really successful or influential car guys have something in common: the vast majority of them started at the bottom, sweeping floors and doing the grunt work, and climbed the corporate ladder to the top. After investing 30 years of your life building something, you naturally make decisions with long term success as the goal. Now, too many plans are made with the next investor payout or bonuses as the deciding factors.

End of rant.
 

AuroraGirl

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Read Lee Iacocca biography, he discusses how painful it was to sell the tank contract.

I’m paraphrasing because it’s been several years since I read the book, but he explains that by selling the contract for the tanks, he was giving up a guaranteed 600 million in profit, in a market that by law the Japanese weren’t able to compete with.

If you haven’t read his biography, it’s very interesting. It’s also very depressing, because a lot of what he predicted 40 years ago happened.

As someone who has studied the automotive history, it seems the really successful or influential car guys have something in common: the vast majority of them started at the bottom, sweeping floors and doing the grunt work, and climbed the corporate ladder to the top. After investing 30 years of your life building something, you naturally make decisions with long term success as the goal. Now, too many plans are made with the next investor payout or bonuses as the deciding factors.

End of rant.
being fired from ford would have sucked but frankly it was too his benefit , who wants ot hang out with the egomaniac ****-grandson blowhard
 

Matt69olds

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being fired from ford would have sucked but frankly it was too his benefit , who wants ot hang out with the egomaniac ****-grandson blowhard


Iacocca mentions in the book the The Deuce was not happy about the Chrysler presidency. His thoughts were most people retire and hang out on a golf course, never to be heard from again. Iacocca was motivated, Ford was paying him a lot of money to go to work to kick their ass.

If anyone has any interest in the glory days of the auto industry, I’d recommend reading his books. While not an auto executive, Jim Wangers had a huge influence on the auto industry as well. His book describes his efforts to market the auto industry. Bob Lutz, John Delorean, Dale Smith, the list goes on.


Glory Days: When Horsepower and Passion Ruled Detroit
https://a.co/d/e1ovmeQ


Iacocca: An Autobiography
https://a.co/d/gIf7skO

Racing To The Past: Oldsmobile and Its Demise
https://a.co/d/094Qr05
 

AuroraGirl

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Iacocca mentions in the book the The Deuce was not happy about the Chrysler presidency. His thoughts were most people retire and hang out on a golf course, never to be heard from again. Iacocca was motivated, Ford was paying him a lot of money to go to work to kick their ass.

If anyone has any interest in the glory days of the auto industry, I’d recommend reading his books. While not an auto executive, Jim Wangers had a huge influence on the auto industry as well. His book describes his efforts to market the auto industry. Bob Lutz, John Delorean, Dale Smith, the list goes on.


Glory Days: When Horsepower and Passion Ruled Detroit
https://a.co/d/e1ovmeQ


Iacocca: An Autobiography
https://a.co/d/gIf7skO

Racing To The Past: Oldsmobile and Its Demise
https://a.co/d/094Qr05
Thank you
 

bucket

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No, sorry - i wasnt referring to you questioning me...i generally advise against leaving the 1-2 acc piston out when converter stall and trans are stock out for two reasons:

1. The delta in shift firmness with it removed is usually too aggressive, esp in a lighter weight vehicle (ie Nova) compared to a squarebody truck and can make the vehicle borderline undriveable for most

2. The th350 1-2 accumulator's job is to soften shifts by slowing the speed of the shift down so the intermediate roller one way clutch (OWC) can go from freewheeling to fully holding before the intermediate clutch pack fully applies. If the clutch is at full compression before the intermediate OWC is holding, the OWC and/or outer race can break.

In a high stall application (3500+ generally speaking), the much looser converter absorbs most of that shift energy hence why its much safer to leave it out (and block the 2-3 accumulator and dual feed the high clutch).

The above also broadly applies to the TH400 and 4L80E.

In your case, assuming your converter is stock, id drop the valve body and see what the 1-2 and 2-3 feed hole sizes in the spacer plate are drilled to (if at all) and open those up a little bit first. A modest increase in feed hole size will make a big difference if the plate hasnt been touched while not putting that OWC in any danger of breaking...let me know if want to get into it and ill help out however I can.

So I finally got around to replacing the rock hard o-ring seal for the 1-2 accumulator. When I removed the cover, I found that the spring was actually broken. It is an orange colored spring, if that matters. Not having a replacement spring handy, I put it back together how it was. I'm guessing that overall length of the spring is 1/4" shorter than it's supposed to be. It shifted smoothly before, I assume it still does. Will the installation of a new spring make it shift even softer than it does already?
 

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So I finally got around to replacing the rock hard o-ring seal for the 1-2 accumulator. When I removed the cover, I found that the spring was actually broken. It is an orange colored spring, if that matters. Not having a replacement spring handy, I put it back together how it was. I'm guessing that overall length of the spring is 1/4" shorter than it's supposed to be. It shifted smoothly before, I assume it still does. Will the installation of a new spring make it shift even softer than it does already?
I would think it would shift more consistently with a new spring in addition to being softer.
 

HotRodPC

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So I finally got around to replacing the rock hard o-ring seal for the 1-2 accumulator. When I removed the cover, I found that the spring was actually broken. It is an orange colored spring, if that matters. Not having a replacement spring handy, I put it back together how it was. I'm guessing that overall length of the spring is 1/4" shorter than it's supposed to be. It shifted smoothly before, I assume it still does. Will the installation of a new spring make it shift even softer than it does already?
Very common to find them broken. I'm sure the difference is the strength, but IIRC, there's an orange spring, and a purple spring. I'd say about 75% of the time they were broken. Most of the Th350's I build were for the street race guys so I always kept them anyway and then when I'd do an OE build, I'd replace the broken spring with a used good one. Figured if it last that long, it was a good spring and would continue to last.
 

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