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I have my 1979 Chevy k10 4x4 with a 350 small block 5.7. It has a a 350 turbo on it that just blew so I want to throw a 700r4 in there for better gas mileage. And I would like the overdrive. But I want to know what all I have to do to put it in there? I know its electrical so I gotta put some type of computer on there. Do I need a brand new transfer case or can I use the one I have hooked up to the 350 turbo right now. Just the whole process of how I need to do this would be nice. Pictures and links help a lot. Thank you!
 

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Only thing electric on a 700 is lock up and a few companies make lockup kits for them, you will need to change the throttle arm(not sure of actual name) on the side of the carb, you will need the tv cable mount for the intake also. Not much help on the tcase sorry.
 

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Mmm Sandwich
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Make sure you adjust the TV cable correctly or you will trash your 700r4
 

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You will need the flywheel for the 700R4...you will need the starter for the 700R4...you will need the torque converter for the 700R4...you will need the output shaft housing from your current TH350...you will need a dual socket brake pedal switch...you will need your current drive shaft shortened...you will need to drill new trans x-member mounting holes...



You will NOT need to install a computer of any sort.

Basically, here it is in a nutshell:

1) bolt the 700R4 flywheel onto your crank shaft.
2) Install the starter which was used with the 700R4 onto your engine. Some people got the idea that you can use your original flywheel and starter and....whatever...NO....it wont work...you are dealing with metric measurements here and your 70's flywheel wont bolt up to the 'metric' torque converter.

3) Install your 4X4 tailshaft housing onto the 700R4...this will give you the ability to continue using the mechanical driven speedometer as well as allow you to bolt your T-case onto the 700R4.

4) Have your driveline shortened EXACTLY 3/4 of an inch. Any more than that and you may crack the tailshaft housing as the rear suspension travels in its telescoping motion....any less than that and the slip yolk will bottom out and trash your output shaft seal.

5) Buy the appropriate conversion kit which allows the transmission to operate correctly...there's dozens of company's out there selling these things....average price of a kit is right around $130...it will come with wires, sockets, a servo, a pressure switch...if you get the most complete kit it will also come with new pan gasket and filter.

6) Once the transmission has been prepped and installed onto the engine block, you will need to bolt the trans x-member to the trans mount...at this point the trans x-member to frame bolt holes wont line up. You will need to position the x-member within the frame rails (whilst it's bolted to the tranny mount) and drill out new holes in the frame to secure the x-member.

As some extra info....The 700R4 trans bellhousing was designed to be used with "regular" V6 and V8 engines as well as "vortec" series engines, so in the future, if you want to upgrade your 70's motor to Vortec, you'll be one step ahead of the curve.

Basically.
 

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Probably the most informative old ass thread bump Ive ever seen.
 

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700's suck. save your time and money and rebuild the 350.
 

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I swapped a 700 into my truck and pulled a 350 to get OD and a lower first gear. The two trans were same exact length (350 w 9" tailshaft), same slip yoke spline count (30 IIRC) same trans mount location and same flex plate as the 350. A very easy swap overall. Adding lockup and unlock was easy too.
With the proper TV setup (using a pressure gauge) and a careful eye on trans temp/cooler this thing has been bulletproof.
I'm not sure about what mods are needed for a 4x4 application but its been done before and parts should be out there.
If I were to hate on the 700 I'd probably build a 400 rather than a 350 for HP application.
 
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