I think I will use this method so I dont fry my new 700R4. I think I would install the gauge before I place the trans into final position.
From Page62 a while back:
To adjust the TV cable, you MUST have a tranny pressure gauge. NEVER use the WOT method of adjusting the cable. Period. You're going to use the black plastic adjuster to set TV pressure at idle (with a warm tranny). What you do is move the adjuster forward until the pressure drops and goes down no further. Then start moving it back until pressure increases 2 psi -- that's it, just 2 psi. Then lock it down and test drive the car. If it shifts OK, remove the gauge and enjoy driving
Some general questions on this adjustment.
1) Does this test port leak fluid when the gauge is removed and the plug is still out?
2) Is there a method that works best to access this area once the trans is installed? Im not sure if I can even SEE it!!
1) yes, when you remove the gauge and/or plug it will leak fluid. It won't leak much without it running, but dont start it with the plug out unless you wanna have one hella mess to clean up.
2) i can't say as i have ever had to check line pressure on a 700 in a c3, so im not much help there. just by using my imagination, id say its doable, but probably not too pleasant.
i have installed numerous 700s over the years, and have always used the WOT method to set line pressure. or at least started there. and then adjusted it by feel. i have checked line pressure during this procedure, but only it i suspected something was wrong or it didnt feel correct. im certain setting it with a gauge is probably the most correct way, im just saying i havnt had any trouble.
now, that is based on everything involved is as it was designed to be. at WOT the cable is then pulling the linkage in the trans to max travel causing the valve to be pushed in as far as it will go. this means max pressure is achieved at wot. then, by design, as the throttle angle is lessened, pressure will drop as needed. so, basically, what you have is the cable that is taunt at wot. that is just as far as it can go. any tighter and youll fold up the linkage in the trans.
now, if you are dealing with a non OE design, it can be a bit touchy. travel and geometry become a factor. so at that point, keeping an eye on your pressure might not be a bad idea if you are not comfortable and/or confident in adjusting without it.
keep an eye on your min and max travel of the cable. you might have to relocate where it attaches to the throttle arm to get the geometry you desire. that way you take full advantage of the range of pressure.
FYI: a lot of people want to adjust the tv cable to change the point at which the trans down shifts or up shifts. the tv set up on a 700 controls everything at the same time. granted, it will have an effect on this, but its not like the kick down cable on a 350 trans or the solenoid on a 400. and as far as upshift, it is a bit more difficult to "dial" it in on a 700 compared to a vacuum modulated unit. where you can manipulate the adjustable modulator to get it right where you like it. so, when it comes to shift "feel", you will have to settle a bit with what ever it gives you. unless you wanna do a bit of governor work, and valve body work, which is horse of a different color.
and lastly, make sure your cable operates smoothly and doesnt catch or hang up. it should require little effort to pull the cable all the way out, and it should retract on its own.
I can access the test port in my 76 just fine...its tight but you can get to it.
One word of caution...don't drive around with the gage installed to long....don't ask me how I know this...the fitting isn't really rated for continuous high pressure use.
This is the proper method for setting the TV cable (700r4 and 2004r alike), but you also need to make sure that at WOT the plunger is completely depressed in the valve body. Seems like a never ending battle but if you can find the happy medium it will work just fine. Once you have the pressure set you should remove the pan and have a buddy press the gas pedal to the floor (engine NOT running of course). Then check two things...is the carb really at WOT, and how far did the plunger depress. The end of the plunger should be even with the end of the sleeve it slides in. If its close adjust the cable one or two more clicks to get it fully depressed. Then put it together and check your idel pressure again. if its within 5 psi of the pressure when the cable is unhooked (ie the cable is removed from the carb), then you should still be right where you want it. Also check everytime you adjust something that when you just touch the throttle that you get an instant pressure increase.
The best kit I've found to ensure that the plunger depresses completely is from Bow Tie Overdrives. The simple lever arm on a standard carb doesn't always have the right amount of pull to achieve this. Bow Tie OD employs an elipitcal cable quadrant to achieve a consitant even pull of the cable. The straight lever arm tends to change rates and amount of pull over the entire sweep of the throttle. The quadrant will keep the pull point in the same spot over the entire sweep.
Either way though you should check the function as I stated...the main reason these transmissions didn't perform as well as expected was because of the factory linkages...make sure it opens the tv valve all the way. That's why the factory setting is supposed to be "pull back the cable and then push the pedal to the floor". This would guarantee that the valve is open all the way but it doesn't make sure that the pressure at idel is correct or that it would make for an instant pressure rise.
If you had the transmission rebuilt and the rebuilder changed the spring for the tv system there is a good chance you're going to need to verify full functionality of the system not all springs are equal and it can have adverse affects on how long that transmission will live. I highly suggest reading Bow Tie Overdrives website, especially when it comes to how the TV system operates and what its supposed to do.
Work was done by this shop: Bendtsen’s Transmission Adapters
A $1295.00 Street Rod 700R4 transmission from Bendtsen's Transmission will have the following components installed if you have 350 HP or less.
8 Friction 3-4 clutch assembly (Z-pak)
High Energy band
10 vane pump w/.471 boost valve (13 vane pumps have lower volume)
New tall low roller clutch assembly
6 low-reverse frictions
Improved sun shell
New 29 element sprag
New Torrington bearings
Corvette servo and superior 4th piston
Transgo shift kit & new accumulator pistons
2000 stall converter with furnace brazed turbine and impellor, all Torrington bearings, hardened turbine splines, H/D lockup clutch
I did the whole pressure gauge thing with my 700r4 but in the end it self adjusted to the plunger fully engaged at WOT since the plastic adjustment bracket slid back on it's own while depressing the throttle. I think the pressure gauge is basically a waste of time and money as long as you set the TV cable tight enough initially so it does the self adjustment.