700r4 tv cable

[lowbudget50]

I built the bracket for my 50 with the tri power on it. Havnt had a problem. My tranny guy said to check the cable for correct pressure, take off from a stop at about 1/4 throttle.. the tranny should shift out of first gear at around 10-12 mph. Mine works great, best mod i ever did to the truck

 

[Skip]

I was making a bigger deal out of it than it was Skip. Then i thought the overdrive was yet another cable. It's all uphill when you are dumb.

Before a few of the big kids here got me lined up with the information I needed, I was contemplating ditching the transmission for a th350. Its all a learning process. Especially when we have to use newer vehicles and parts than we grew up with to cobble together a new toy. Dumb people don't ask questions.

Put me on the waiting list to see what you are doing with this project.

 

[Bamamav]

It is NOT a kick down cable like the TH350 or TH400. The TV cable on a 700r4 or 200r4 controls line pressure as well as shift points. This is why when you adjust the sheath away from the throttle it firms up the shift. If you drive it around unhooked you will be making shifts at the minimum line pressure. Think of what will happen to your clutch packs if you do a couple of wide open up shifts with the equivalence to an idle speed line pressure. Not good. Get a bracket made for the carb and a 700r4 and adjust it correctly. It will save you a ton of grief down the road. [P

Dumb question--What would happen if you simply blocked the cable at full pull, thereby having full line pressure at all times? I have seen kits on Summit that basically do the same thing, put full pressure to the valve body. I would think it might "bang" when you shift into drive from park, but other than that, what would happen?

The first Vette I bought, a 84 Cross Fire that had been converted to a Edelbrock carb, the cable wasn't hooked up properly, they had just tied it to the linkage. Needless to say, the trans started giving problems right after I bought it. If I had of noticed it, I would have passed on it. I bought the geometry corrector and bracket and hooked the cable up properly, but it was too late. Overdrive would work when the trans was cold, but when it warmed up, it would never shift into OD. Instead of fixing the trans, I sold the car. I'm thinking one that had full line pressure at all times might work better?

 

[tmgant]

The trans will then think the engine is at wot,, so the governor psi will have to overcome the shift valve,, gov psi is 1psi per 1mph +/-,,,,the shift valve has tv psi against a certain valve bore size ,, gov psi is against the shift valve with a certain bore size,,, gov psi has to move the valve to shift,, so at wot the trans will not shift below 40-45mph,,, this is the basics,, I have been in the trans world for 35 years ,but I still learn something new everyday,, Tobby

 

[Bamamav]

So are you saying Tobby that it wouldn't shift out of low until 40-45 mph then? Be kinda rough in city traffic that way. I too have learned something today.,..

 

[tmgant]

Yes it controls line psi and shift timing , the constant pressure valve bodys you see for sale control line psi only , you still have to run a cable for shift timing. Tobby