700r4 with TBI motor, non ECM controlled lock up???

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usar17

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OK so i put a 350 TBI motor in my truck. Kept the 700r4. My question, that i see bucket askes alot with no answer, Where do i run the vacuum line from the lock up switch? Originally it runs through a TV on the intake manifold. Now how should i run it since there are no vacuum TVs?
 

Jims86

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OK so i put a 350 TBI motor in my truck. Kept the 700r4. My question, that i see bucket askes alot with no answer, Where do i run the vacuum line from the lock up switch? Originally it runs through a TV on the intake manifold. Now how should i run it since there are no vacuum TVs?

You can run it from manifold vac. The reason for the TVS on the carbed engine, is beacause if the Trans locks up before the engine is up to temp, it could kill the engine, so the TVS delays that, and is opened only when it senses proper temps.
 

usar17

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...is that gonna be an issue not having temp control? And what is the little thing that reduces the vacuum line size? Is that a delay or check valve?
 

Jims86

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...is that gonna be an issue not having temp control? And what is the little thing that reduces the vacuum line size? Is that a delay or check valve?

May be a delay...dont want a check valve on there. Wont be an issue, because you have injection now...fuel is atomized a little better, and you have an ecm that can control the Idle bypass air and fuel ratio. Unlike a carburetor, and even a computer controlled carb.
If you find that you want Computer cotrolled lockup, its easy to make a harness to do so, and I think I have a chip you can have to control it. T
you can buy the plug for the trans end, and then its just 3 wires to the ECM, and one to a brake switch, which you may already have if your truck originally had cruise.
 
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usar17

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lemme see if it will lock up in the current set up. Still hammering out small bugs ;)
 

usar17

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TBI350/700r4/NP208
Also, My Flywheel/Torque Converter Inspection cover is rubbing the fly wheel. Any thoughts why? I had to shave it just to fit bc the oil pan on the 350 was hitting. What was different between the 1985 305 and a 87+ 350?

PS: there are some thoughts this motor was in a van
 

Jims86

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Also, My Flywheel/Torque Converter Inspection cover is rubbing the fly wheel. Any thoughts why? I had to shave it just to fit bc the oil pan on the 350 was hitting. What was different between the 1985 305 and a 87+ 350?

PS: there are some thoughts this motor was in a van
in 86, GM switched to a one piece rear main seal...85 was 2 piece. maybe a different inspection cover for 87. I dont think the oil pans interchange either, so that could explanethe clearance issue.

Yup, it was a thought I had, because of the van type throttle body where the throttle cable snaked around to the front.
 

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