700r4 pressure questions

I have a 700r4 I am in need of answers. I have a 300psi pressure gauger hooked up and checking pressure readings, in park with the TV cable not attached I get a reading of 130 to 140, the needle bounces between the to. When I put it in reverse it drops to 60 for a second and jumps to 225 and bounces between 225 and 240. If I put it in drive, does not matter which gear it stays bouncing between 130 and 140. no pressure change. If I hook up th TV cable and adjust for the 3 to 5 psi and recheck the pressure readings they are all the same as mentioned . Just a note this trans has a corvette servo and a aftermarket accumulator spring. No I did not install any of the parts, it's a trans I bought from Jackson Performance. The trans seems to shift OK but I want the TV cable adjusted correctly. Can anyone give me some input. :whacked:

There's some very good information on this site also. Check the menu at top left of the page.

http://www.tvmadeez.com/tvinstadj.php

http://www.tvmadeez.com/tvinstadj.php

Thanks for the information, I'll see if helps .

I'm putting a 700r4 in a 77 corvette, and taking the 350 out... looking for better mpg... gas is only 3.20 now. I've been kind of worried about all the stuff I've read about the tv cable (at first I thought it had something to do with my television... not really a tranny guy). soooooo, how critical is it to take it to a tranny shop to get the pressures checked. Its a used tranny, and my concern is the tranny shop will start to sell me a bunch of stuff that's not really needed, since it's obvious I don't know much about trannys. reading the range from the lowest min. to the highest max pressures is a wide range... kind of makes me think, getting a precise pressure is not that critical. It helps to know that more is better when it comes to pressure... thanks for the help - kbyounger