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I currently have a TH400, and w/4:10 gears it's just no fun going down the highway. I would like to swap to a overdrive transmission. What is the best transmission to look at that would be more or less a direct swap out? I really dont want to have to add any electronics if I can help it. Also what manufacturer/builder do you recommend. My nova has a Big Block w/approx 500hp. Thanks for the help.
 

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Mike - 74 Nova Baltimore, MD
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Both the 2004r and the 700r4 automatic transmissions would be a direct swap-out (with one 12 volt wire connected to the transmission's "lock-up" switch).
I run a 2004r transmission behind a sbc 400 with approx 500hp. I also have 4.10 gears and cruise the highway at 70mph @ 2450 rpm. I like the gear ratio spread of the 2004r vs the 700r4. The 2004r also has a slightly better overdrive gear vs the 700r4 (.67 vs .70).

With the hp and torque of your big block, you will probably need a "built" automatic overdrive.
I purchased my 2004r from CK Performance.
2004R Transmissions
But I also recommend Extreme Automatics for a built 2004r.
Both of these guys know what they are doing... and are highly recommended by the members on the Turbo Buick forum.

I also installed a 2800 stall "Lock-up" Edge Racing Converter (Street Edge) and I am very happy with how it performs.
Feels like a stock converter under normal starts and cruising... but you know it's there when you stomp on the gas! What ever you do, don't get an "off the shelf" torque converter.

I was able to reuse my existing driveshaft, B&M QuickSilver shifter, and the transmission cooler lines (with some slight bending). You may also be able to reuse your existing transmission crossmember with the 2004r... since you already have a turbo 400 crossmember.
 

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4L80e is basically a th400 with O.D.
It would handle the power in stock form. Requires relocating xmember and shortning driveshaft. llso requires contoller but can be operated with a simple manual shift box ; transmission functions like it has a full manualvlalve body. PM me if interested.
 

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4L60/4L80 or like are out since you don't want the wiring/controller.

Soooo
either a 200r4 or 700r4 are your most likely candidates. You can find them darn near anywhere and get pretty reasonable quotes to have one built up pretty good from a local trans shop vs buying a "built" unit online.
Depends on your rear gear and tire size. The difference in 2-4th gear on the 220r and 700r arent much different but 1st gear could be a problem if you have a short rear gear like 4.xx. Anything final drive shorter than say a 3.55/26.5" tire, I would go with a 200r. Not that the 700r would be bad, just preference.
 

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You will be happy with a 700r4. You have a heavier car / engine as for me with a convertible 62 with a small block I have a 200r and love it.
 

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If going with the 700R4 I would go ahead and upgrade it with stuff like a aftermarket sun shell, Extra clutch disc and a constant pressure valve body. The lock up feature is pretty simple to do with a vacuum switch that will probably come with the kit.
 

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Both the 2004r and the 700r4 automatic transmissions would be a direct swap-out (with one 12 volt wire connected to the transmission's "lock-up" switch).
I run a 2004r transmission behind a sbc 400 with approx 500hp. I also have 4.10 gears and cruise the highway at 70mph @ 2450 rpm. I like the gear ratio spread of the 2004r vs the 700r4. The 2004r also has a slightly better overdrive gear vs the 700r4 (.67 vs .70).

With the hp and torque of your big block, you will probably need a "built" automatic overdrive.
I purchased my 2004r from CK Performance.
2004R Transmissions
But I also recommend Extreme Automatics for a built 2004r.
Both of these guys know what they are doing... and are highly recommended by the members on the Turbo Buick forum.

I also installed a 2800 stall "Lock-up" Edge Racing Converter (Street Edge) and I am very happy with how it performs.
Feels like a stock converter under normal starts and cruising... but you know it's there when you stomp on the gas! What ever you do, don't get an "off the shelf" torque converter.

I was able to reuse my existing driveshaft, B&M QuickSilver shifter, and the transmission cooler lines (with some slight bending). You may also be able to reuse your existing transmission crossmember with the 2004r... since you already have a turbo 400 crossmember.
Will a 2004R replace my th350 and use existing mount, shifter, cooler lines? I also run 4:10 gears with a small block and am ready for a change.
 

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Mike - 74 Nova Baltimore, MD
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Will a 2004R replace my th350 and use existing mount, shifter, cooler lines? I also run 4:10 gears with a small block and am ready for a change.
The 2004r will bolt right up to the small block (and big block) Chevy.
If you are replacing a th350 with a 2004r, you will need a new transmission crossmember (2004r trans mount is farther back than the th350). I used the G-Force crossmember. You will need a TV cable, TV cable holder, and the correct TV geometry corrector bracket (depending on carb).
Correct adjustment of your TV cable is a must. You will also need a new torque converter.

The existing th350 transmission cooler lines should still work... but you may need to do a little bending where they attach to the 2004r transmission. Just be sure to confirm you have the correct fittings installed into the 2004r trans. IIRC, I just took the ones I had in the th350 and installed them in the 2004r.
If your th350 had the short (6") tail housing, you should also be able to use your existing driveshaft. You will need to look into the specifications of your shifter to see if it is compatible with the 2004r.
 

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Discussion Starter #9
4L80e is basically a th400 with O.D.
It would handle the power in stock form. Requires relocating xmember and shortning driveshaft. llso requires contoller but can be operated with a simple manual shift box ; transmission functions like it has a full manualvlalve body. PM me if interested.
Would/Does a 4L80 require any modifications to trans tunnel?
 

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In theory if a th400 fits then so will a 4L80e. In my 63 I had to do some massaging in one area on the passenger side.
Cooler lines are another problem but this can be solved by using 90* banjo syle fittngs which are avalible specifically for the 4L80e.
 

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Hi Guys speak to Bowtie overdrives I had a 700r4 from them and even though i am in the UK they gave me great service they told and sold me everything i needed to fit one to my 63 wagon their web site is also a mine of information.

Cheers Ian ????????
 
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