700R4 Information Thread

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RanchWelder

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new plan ,ill let you have a th200 for 1000. Its good, I swear

Just dont pay attention to the missing -4r, its good. I swear
Way to go "Swifty"!

You'r cred rating just hit the crapper. :Big Laugh:
 

Ricko1966

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I have a question does anyone know what valve body mods are needed to make a constant pressure throttle body for a 700r4? TCI used to offer one,but no more, now you have to buy their transmission to get one. The idea here was the valve body pressure would never drop below a certain pressure idrc the psi. Anyway even with a misadjusted TV cable pressure was never low enough to hurt the transmission. I'd be interested in building one. I see them on ebay,but TCI no longer offers them,which leads me to believe these are home made modifications. I don't particularly trust ebayers to sell me modified parts.
 
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NickTransmissions

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I have a question does anyone know what valve body mods are needed to make a constant pressure throttle body? TCI used to offer one,but no more you have to buy their transmission to get one. The idea here was the valve body pressure would never drop below a certain pressure idrc the psi. Anyway even with a misadjusted TV cable pressure was never low enough to hurt the transmission. I'd be interested in building one. I see them on ebay,but TCI no longer offers them,which leads me to believe these are homered modifications. I don't particularly trust ebayers to sell me modified parts.
You basically have to block the TV Boost valve so it's wide open and same with the TV limit valve. You also need to modify the reverse boost valve to avoid a severe overpressure condition when in Reverse. I think I have some instructions Chris at CK gave me a few years ago so if I can dig them up, will post them here.

That said, I wouldn't do a CP VB for street use - that much pressure is generally harmful for the pump. If it's race only, it's good to go since trans periodically comes out for refresh in racing applications.
 

Ricko1966

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You basically have to block the TV Boost valve so it's wide open and same with the TV limit valve. You also need to modify the reverse boost valve to avoid a severe overpressure condition when in Reverse. I think I have some instructions Chris at CK gave me a few years ago so if I can dig them up, will post them here.

That said, I wouldn't do a CP VB for street use - that much pressure is generally harmful for the pump. If it's race only, it's good to go since trans periodically comes out for refresh in racing applications.
OK now what if I made restrctors instead of complete blocking so I raise minimum pressure but still have ability for pressure rise?
 
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NickTransmissions

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OK now what I made restrictors instead of complete blocking so I raise minimum pressure but still have ability for pressure rise?
I imagine that could be possible, if you wanted to either make different size restrictors to achieve a certain pressure 'floor' which can be adjusted by either swapping out different restrictors or making an 'adjustable' restrictor...You'll have experiment and test...I'll look into it also and see what can be done.
 

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I imagine that could be possible, if you wanted to either make different size restrictors to achieve a certain pressure 'floor' which can be adjusted by either swapping out different restrictors or making an 'adjustable' restrictor...You'll have experiment and test...I'll look into it also and see what can be done.
Man,if we can figure this out we can save a lot of people a lot of problems.
 

NickTransmissions

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Man,if we can figure this out we can save a lot of people a lot of problems.
I actually set one up for a 200-4R recently so the 700R4 isn't all that different and I imagine will involve the same or very similar steps.
 

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This would be great. I've got mine adjusted pretty good but still not 100% happy with it. I set it up match several articles that said what RPM/Speed it should shift at when at partial throttle but I can't get it to downshift right when I go to full throttle. It's usually not a problem since it's just a cruiser but I sure don't want to kill a good transmission.
 

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This would be great. I've got mine adjusted pretty good but still not 100% happy with it. I set it up match several articles that said what RPM/Speed it should shift at when at partial throttle but I can't get it to downshift right when I go to full throttle. It's usually not a problem since it's just a cruiser but I sure don't want to kill a good transmission.
If you are worried about it,you need to put a gauge on it,which I'd recommend anyway.
 
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RanchWelder

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Adjustable restrictor?
 

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Can you guys tell me what the differences between a gas job 700 and diesel 700 are? I’m going to put a 6.2 diesel in front of one of my known good running 700’s that was behind a 350. I know the converter will be different. But are the governor weights different to lower shift points? Part numbers or a source to just buy everything in one spot would be greatly appreciated. Thank you.

Ben
 

NickTransmissions

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Can you guys tell me what the differences between a gas job 700 and diesel 700 are? I’m going to put a 6.2 diesel in front of one of my known good running 700’s that was behind a 350. I know the converter will be different. But are the governor weights different to lower shift points? Part numbers or a source to just buy everything in one spot would be greatly appreciated. Thank you.

Ben
Governor is the primary difference. The valve bodies themselves are the same between gas and diesel applications...200-4Rs by contrast, use different governors, valve bodies and 1-2 accumulator housings (in case anyone was wondering, lol).
 

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Governor is the primary difference. The valve bodies themselves are the same between gas and diesel applications...200-4Rs by contrast, use different governors, valve bodies and 1-2 accumulator housings (in case anyone was wondering, lol).
Do you have a source for the governor? I’ve done searches online and it always gets off track to billet converters for duramax etc etc.

Ben
 

NickTransmissions

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Do you have a source for the governor? I’ve done searches online and it always gets off track to billet converters for duramax etc etc.

Ben
Buy the Superior Tech governor kit. Should have what you need to adapt your gov for diesel
 

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