Any help finding a vacuum switch from an 81-83'ish model??

[shiner2001]

I normally post over in the 67-72 forum, but have a question for you guys here. In my 64 El Camino, I have a 700r4 that I just had rebuilt and beefed up. This car is heavily cammed and according to my mechanic that did the trans rebuild, the heavy cam and torque converter aren't playing too well together. He says this can be fixed by adding a vacuum switch from what he said was about an 81-83 model Chevy truck. According to him, it's located under the hood on the firewall, just to the left of the steering shaft and brake booster (where you'll find a wiper motor on lots of vehicles from what I gather). He says this switch will have a vacuum line from the manifold on one side and a two wire connection on the other. Can anyone here shed some light on where I might be able to track this switch down? Mechanic says it will be a junkyard find, but I'd sure like to find a new one if possible. And if anyone can give me specifics on the part number/name/years/applications of the switch, that would be a big help if I need to head to the the pick-n-pull.

Thanks in advance guys, I appreciate it!!

[old Rusty C10]

you could try LMC or try the dealer but i too think thats more of a junkyard find too

[shiner2001]

I gave LMC a check when I got home from the shop yesterday, but I didn't turn up anything. If there is any way someone can post a picture or two of this switch (installed and/or removed), that would also help tremendously! Thanks again guys!

[D13]

That switch controlls the TCC apply of a 350C based on vacuum. Others that have used it have been unsatisfied with the behavior of it (still have a lot of TCC hunting). With a big cam and no vacuum it's just going to make you annoyed, everytime you touch the throttle it'll unlock.

A description of what you don't like about the trans behavior will help. Remember, on a 700R4, vacuum has nothing to do with it's shifting or tcc. If you want to delay TCC or only have it applied at cruising speeds there are ways to do that. Like a 35mph governer switch in the trans. Or a 4th gear only switch, a TH400 kick dow wired as an interrupter....

[sumran]

Check here.

http://www.bowtief.overdrives.com/index.shtml

I would talk with Steve. He is very helpful and knows his stuf

[shiner2001]

Originally Posted by D13

That switch controlls the TCC apply of a 350C based on vacuum. Others that have used it have been unsatisfied with the behavior of it (still have a lot of TCC hunting). With a big cam and no vacuum it's just going to make you annoyed, everytime you touch the throttle it'll unlock.

A description of what you don't like about the trans behavior will help. Remember, on a 700R4, vacuum has nothing to do with it's shifting or tcc. If you want to delay TCC or only have it applied at cruising speeds there are ways to do that. Like a 35mph governer switch in the trans. Or a 4th gear only switch, a TH400 kick dow wired as an interrupter....

On the 30 minute drive home from the shop I was honestly not unsatisfied with the transmission's performance. My mechanic's point of view is that it would drive more favorably with the vacuum switch installed, but maybe it comes down to personal preference. I haven't driven the car enough to really experience all the ups and downs, I was just going off of what he said. As far as I'm concerned, automatic transmissions operate off of voodoo and voodoo alone. That's the one part of a car or truck that I won't dive into head first, and my knowledge of how they work and what is preferable as far as options is reflected thusly.