Transmission Options

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Chrono

Chrono

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Well, a few weeks ago, my 74 Duster (slant 6, A904, 7.25 rear) broke its flexplate and damaged the torque converter.
Since i've begun tear down to a shell to do a basic resto-mod, I've also decided to part ways with the 3 speed auto.
I want to get a 4 speed overdrive or 5 speed standard.
Plans are to use it in road course and autocross.
So although i'm not looking to buy right now, i want to compile options and parts lists.
Any info and help is appreciated
 
Chrono said:
Well, a few weeks ago, my 74 Duster (slant 6, A904, 7.25 rear) broke its flexplate and damaged the torque converter.
Since i've begun tear down to a shell to do a basic resto-mod, I've also decided to part ways with the 3 speed auto.
I want to get a 4 speed overdrive or 5 speed standard.
Plans are to use it in road course and autocross.
So although i'm not looking to buy right now, i want to compile options and parts lists.
Any info and help is appreciated
Click to expand...


I went with the 2004R Gm trans. Bought the TCi adapter but I don't know if they make an adapter for the /6. I love the way the car drives and runs. I get great gas mileage and have plenty of power on the low end. Top speed is 175 MPH with 3.73 gears!! You can use a pretty low rear gear (4.10/4.11) with the 2004R trans.

treblig
 
2004R?
Is that in the same family as the 4L60E?
As for adapters for the Slant, I'm doing research on that front, and when I do find one, I'll be sure to make a separate post for our members to reference to.
 
Chrono said:
2004R?
Is that in the same family as the 4L60E?
As for adapters for the Slant, I'm doing research on that front, and when I do find one, I'll be sure to make a separate post for our members to reference to.
Click to expand...

The 2004R and the 700R4 are both non-electronic. The 4L60E is electronic. I always go with the non-electronic trans that way I don't have to worry about wiring and switches to control the torque converter. The 2004R trans fits in the 67 and up A body pretty easy, I made a very detailed thread on the mods and installation of the 2004R in my '69 Barracuda.

treblig
 
Chrono said:
Well, a few weeks ago, my 74 Duster (slant 6, A904, 7.25 rear) broke its flexplate and damaged the torque converter.
Since i've begun tear down to a shell to do a basic resto-mod, I've also decided to part ways with the 3 speed auto.
I want to get a 4 speed overdrive or 5 speed standard.
Plans are to use it in road course and autocross.
So although i'm not looking to buy right now, i want to compile options and parts lists.
Any info and help is appreciated
Click to expand...

The A833 O/D is pretty straight forward, since they were available in A and F bodies. Check out Brewers Performance or Passon Performance. Nothing like a manual transmission with an infinitely variable stall speed.
 
For your application with a slanty, the Chrysler 3 +1 is ,IMO,a terrible option. You will need as many gears as possible.I vote close ratio-non O/D-5speed for a NA slanty.
But if you are going to turbo that baby, then it might work, but it would need specialized tuning. And when you forget it's a 3 + 1, your turbo will blow up that O/D gear.
 
Chrono said:
2004R?
Is that in the same family as the 4L60E?
As for adapters for the Slant, I'm doing research on that front, and when I do find one, I'll be sure to make a separate post for our members to reference to.
Click to expand...

Two totally different transmissions. From the factory, GM typically used the TH2004R behind low horsepower /low torque v6/v8 engines while the 700r4(as known as the 4L60) was used in Corvettes, Camaro's, cop cars, and light duty trucks. Both can be built to withstand more HP than GM intended, but at a cost. Behind big blocks GM used the TH400(3 speed) until the 4L80E(4 speed) came out in the 90"s.
 
AJ/FormS said:
For your application with a slanty, the Chrysler 3 +1 is ,IMO,a terrible option. You will need as many gears as possible.I vote close ratio-non O/D-5speed for a NA slanty.
But if you are going to turbo that baby, then it might work, but it would need specialized tuning. And when you forget it's a 3 + 1, your turbo will blow up that O/D gear.
Click to expand...

Actually the plan is to supercharge it
 
AJ/FormS said:
No, No I mean we haven't heard from you in a while. Over a week
Click to expand...

OHHHHH Lmao!!

Yeah, its just been busy at work and such. And until i get moved, the duster is on ice, so i'm researching. But i'll check in more often
 
Treblig said:
I went with the 2004R Gm trans. Bought the TCi adapter but I don't know if they make an adapter for the /6. I love the way the car drives and runs. I get great gas mileage and have plenty of power on the low end. Top speed is 175 MPH with 3.73 gears!! You can use a pretty low rear gear (4.10/4.11) with the 2004R trans.

treblig
Click to expand...
Are you able to use the OD gear in your TH200 at full throttle high speed? Only reason I'm asking is because when I've had TH200s an TH700s they would not go into or stay in OD past about half throttle. IIRC GM made them like that because the OD clutches and hardware were not beefy enough to withstand high power. That's one big advantage the Mopar A-500 and A-518 have over their GM counterparts, the OD units are plenty big and beefy.
 
Every time I use a 2004R or a 700R4 in one of my cars I install a non-lock up TC. I also use all the "good" parts like hardened drums, etc. If you use a non-lock converter you don't need any switches and wires to lock and unlock the converter. I cars shifts into OD at around 45 MPH and stay in OD unless you accelerate then it will downshift to third gear or second (passing gears) depending on your speed. Once you let up on the throttle it goes back into OD as long as you're going over 45 MPH.
To answer your question directly, YES...it stays in OD to top speed unless you punch it and make it downshift in which case the transmission "thinks" you're passing someone on the highway just like any other transmission downshifts. As soon as you let up on the throttle it goes back into OD.
You are correct, 4th gear wasn't designed for pulling heavy loads. Even modern cars (2016) have buttons (switches) so you can turn off the OD function when pulling a trailer or going up steep inclines.

Treblig
 
trying to find a 4 speed auto or 5 speed to bolt to /6 or an adapter is going to be like finding chicken teeth....damn near impossible...maybe some 4L jeep stuff?
 
magnummopar said:
trying to find a 4 speed auto or 5 speed to bolt to /6 or an adapter is going to be like finding chicken teeth....damn near impossible...maybe some 4L jeep stuff?
Click to expand...

That would still be in the 44 to 46RH family of Chrysler automatics, which i would actually prefer.

As for lock up TCC, i'm totally ok with having it push button operated. It is, after all, getting a rachet shifter if i stick with an automatic
 
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