th400 low shift pionts

5

53BUICK

Guest
Hey guys, Im new to your forum,it looks cool.
anyway, Ive got a 53 buick with a 74 455
and 400 trans. I dont have the kick down installed yet,the 400 uses electric kickdown? so do I wire this so I have 12volts to the trans at full throttle?
my next problem is this trans upshifts very quickly,there is no delay when upshifting(at 1/2 ,3/4 throttle)it will be in 3rd gear brfore you get thru an intersection.I replaced the modulater,no change.Am I correct to assume the kickdown only delays shifts at full throttle? The modulater should still delay shifts at throttle positions less than full.
I also removed the modulater valve in the trans ,it moves freely,do I have a valve sticking in the valve body?(Im an acura mechanic and have rebuilt many acura transmissions but I have no experiance with
REAL car trannys)
smile.gif
Thanks in advance for any help
 
You're in luck (I hope), because I have the excact same set-up (1974 455 w/TH400) with the excact same problem. Here is how I fixed the problem. Did you know that the modulator is adjustable? There is a little hex screw inside the modulator (where the vaccum line connects I beleive). If you turn it clockwise the shift points will move up. But here is another problem, they only adjust up about 5MPH, so this alone didn't solve the problem for me. Guess what did? A shift kit. Now I get rubber between first and second gear! As for the kickdown, yes, you apply 12v at WOT. You can go to this link to find shift kits and other TH400 accessories pertinent to your situation: http://www.tognottisautoworld.com/Products/B-M/page18.asp
Hope all this helps!

[This message has been edited by big_riv67 (edited 04-06-2002).]

[This message has been edited by big_riv67 (edited 04-06-2002).]

[This message has been edited by big_riv67 (edited 04-06-2002).]

[This message has been edited by big_riv67 (edited 04-06-2002).]
 
Big Riv67
Thanks for the info ,I did adjust the modulater and it didnt change. Im going to order a shift kit today and hook up my kickdown.I'll let you know how it works.
Thanks again for the help
53BUICK
 
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