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700R4 lockup

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Cool53:
Wow! Talk about a lot to talk about.
First, TV cable adjustment is easy, it's TV installation that must be right. The cable must be perpendicular to the throw of the throttle arm pickup point, and it must swing in the proper arc. So if you use late model Quadrajet that was used with a 700R4 or a 200R4 you're ok. If you run a Holley or an AFB (Edelbrock) style carb you will have to purchase and install a cable corrector bracket. Once you get the cable happy just set it so that it is tight a wide open throttle and adjust it back and forth a click at a time until you get the shift points where you want them. If you have to go more than a few clicks then it I time to start modifying the governor springs, or changing the governor itself to a Corvette style and changing springs on that. I can give you more if you need it. If you run an E transmission, such as a 4L60E then you don't have these issues.
More on this later if you need further explanation.

Can I run without the converter clutch locked. The answer is a definitive YES if your trans is a 1985 or later, and if your hotrod is light weight and you aren't into delivering Abrahm's tanks the the early ones are ok, too. The only time you can run into trouble because of not locking the converter is if you have a heavy vehicle, under a constant heavy load, with a marginal cooler. Again, you should run trans temp gauge if you red worried about overheating the transmission. If you run n E trans it incorporates a thermistor in the internal switch plate which can be read through the controller or scan tool. The post 1984 transmissions routed more cooler oil through the radiator when then TCC is engaged.

The wiring for the TCC is something you have to know from the builder. I wire all of the transmissions I sell with the grounding switch in the fourth gear circuit of the valve body providing ground. I don't need or want the TCC on until fourth. If you look at 700 wiring schematics you won't believe how many different schemes the factory had over the years. To operate the clutch you should need to provide B+ to I the correct terminal on the trans! I always use the right front terminal, interrupted by the brake switch, and I some cases a vacuum switch. But the vacuum switch needs to be adjustable because every car is different and every driver want something different. For those reasons I tend to not use the vacuum switch. You can have a TCC circuit that works electrically and hydraulically that doesn't seem to work which could be for a worn out clutch disc a failed converter, or maybe just the little I seal on the turbine (input) shaft. You can check to see if the circuit is working by connecting a pressure gage into a cooler line and watching for about a 25 psi pressure drop when I the TCC is commanded on.

These explanations are going to raise a bunch of questions, and that's good. And my typing isn't all that good on this iPad, so I am going to use the computer for now on!!

If you are going to build your own transmission I recommend Transgo kits. They have the TV circuit down to science and when you re done it works perfectly. If you want to keep from getting covered with trans fluid from modifying governors the consider an E transmission.

EDNY:
Jef


Sure am glad you decided to participate in our forum.  I'll probably be bugging you with 700R4 and 4L60E questions.  I have been hoarding post 1988 700R4's and 4L60E trannys..have a nice collection in my barn - some work - some for parts.

Didn't realize I could get a Transgo rebuild kit "with torque converter" for about $350 delivered. They sell the Corvette servos for about $13 delivered.

Thanks again
Ed

Cool53:
Hey Ed,
Any of you that need parts can get them from Dean Transmission in Agawam, MA . Extension 118 will get you Debbie, she's my salesperson.

Cool53:
I also collect as may 700's as I can find. It is only part of what I do here, but I still sold over 30 last year. I had a bone stock on in my truck with good clutches and a B&M kit and I raced it and drove it for 30,000 miles, now it's in my friends '34 with a very healthy 406 and is still working perfectly. But no one is going to sell you a 700 or a 2004R that is going to shift just the way you want it, you have to play with tad cable and the governor to get it just right. If you're mot fussy then it makes it a lot easier. Because I race my truck I used to shift it manually, but with an E transmission I just program it to shift at 7200 and leave it in drive.

Cool53:
If you are interested in performance you can't pick a carburetor without knowing rear fear, converter stall speed, and all that stuff. I'll put something together for that soon. I'll discuss the difference between racing converters, street converters (flash converters) and stock. And why you can run a high stall converter with a 2.73 rear gear.

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