85cmroz28

I am in the process of retrofitting the TCC on my 700r4 to lockup without the computer. So far, I have installed a vaccum lockup switch and ran wire from the switch to a ground and the brown and black TCC wire on the ALDL. Everything is hooked up, but the convertor will not lockup. I know that the wiring is right because it worked when I put a manual switch in place of the vaccum switch.

I have 2 questions:
1. Which vaccum line should I have tapped for the switch(right now it's running off of my brake booster)? I wasn't sure whether to tap the brake booster or the hose going to the distributor.

2. Is there anywhere I could find a connector for the vaccum switch(I just soldered it the best I could)?

I appreciate the help!

Apeiron

Factory non-computer TCC setups used a ported vacuum source. If you don't have ported vacuum then it makes no difference to the TCC where you get it from, but connecting anything to the brake booster line probably isn't the best idea.

What vacuum switch are you using?

HalfInchWrench

The vac switch was off the EGR vac line on non CC Canadian cars as in this diagram. Not sure if this method was used on any US cars.

85cmroz28

I should also mention that I do not have the stock q-jet and I got rid of the EGR. The switch came stock on 82 and 83 Camaros with the 200c tranny. This should work with the 700r4, right?

Apeiron

That switch will work fine, and you don't need EGR you can use any source of ported vacuum.

85cmroz28

Sorry if this sounds like a stupid question, but, what's the difference between ported and manifold vaccum and where exactly should I hook my switch.

thirdgen88

Ported vacuum recieves a vacuum signal off-idle.. Meaning you won't have vacuum at that hose when the engine is idling (if you do, it will be a very weak one). Manifold vacuum means you have full manifold vacuum all of the time... Anytime there is a change in manifold vacuum, that hose will see it.

85cmroz28

Thanks for the reply, but the question I was really trying to ask was where on my car can I find a source of ported vaccum for my switch?

Thanks

Apeiron

Find a ported vacuum port on the carb. Try the one that used to be connected to your EGR.

thirdgen88

Look for a port on the carb that is higher then the level of the bottom butterflies, that will usually be ported vacuum... You could also find one pretty easily by running the engine and looking..

85cmroz28

The only port I found above the butterflies on my carb is connected to the distributor. Would it hurt anything to just T it off?

HalfInchWrench

Go ahead. That will work. Wouldn't hurt to size up your carb either to see what your EGR source was. When folks go in and tinker with stuff, sometimes they make a mess. Good to see what has been butchered or done right.

85cmroz28

I've tried everything guys. I've hooked the switch up to ported vaccum, then I tried manifold again. Nothing will make my TC lockup? Am I missing something here????

85cmroz28

Update: I got the problem solved...it appears that the connector on the transmission likes to work it's way off whenever I hit a bump...but I fixed it so it won't come off again.

All in all, not bad...saved alot of money when you compare it to the TC Lockup kit in Summit($127.95). I paid $27.00 for the vaccum switch, $3 for the connector(junkyard), and $3.97 for butt-splices.

mdricken

Where did you get your vaccum switch? Is it just called a "TCC vacuum switch"? Thanks.

Apeiron

Ask for P/N 14014519 at your favorite GM dealer parts counter.

85cmroz28

that's the P/N...very easy to install- if you have any questions just ask

HorseflyDF

I dont have a cpu in my car
how can u make a switch from the adl connector I thought the cpu sends power to the circuit? Is this a bypass for the circuit ?


I didnt even know theres a vacuum line
involved, for locking up the converter.


I dont chit about auto trannys
I dont understand what the torque converter exactly
does and how it feels when the car is locked up.

bluegrassz

iTrader: (3)

thanks for the part# and the heads up on the swap guys!!

I might try this setup for my car.

85cmroz28

The torque convertor connects the engine to the transmission. It's pretty much a fluid-filled cylinder with 2 propellers on each side. When the engine turns at the correct RPMs, the spinning of the engine side propeller will spin the transmission side propeller- which will turn the transmission. When this happens, since it is the fluid doing the spinning, there is naturally some slippage between the engine and the tranny. A torque convertor lockup switch will make the torque convertor directly connect the engine to the tranny.
HorseflyDF- there is always power being sent to the tc lockup, but when you connect the 2 wires on the ALDL, it ground the tc lockup, causing it to lock.

My GM Dealer wanted like $60 for the switch- I found it at Advance Auto for $25- just give them the GM P/N.

HorseflyDF

thanks
i will check the aldl terminals for power.

Why did u need to buy a special switch if all you have
to do is connect a and f to lock the tcc?

Is that because you have a vacuum to lock the tcc?

Apeiron

The vacuum switch is to unlock the converter automatically near WOT.

HorseflyDF

So if your car came out of the factory
with a cpu the car would not have a vacuum switch
to unlock the converter at wot.. correct?

Apeiron

Right

HorseflyDF

thanks
now I dont have to search for something that
doesnt exist.

85cmroz28

As a side note, I have found(and TCI and PAINLESS have also confirmed) that these TC Lockup vaccum switches work best with manifold vaccum. On most Holley carbs, there is a manifold vaccum connection right under the primary fuel bowl on the throttle body.

Apeiron

I'd still rather use ported.

Andy89GTA

Guys, Can you tell me which 2 pins on the ALDL to connect to get the TCC to lock up? Thanks!

Andy89GTA

Nevermind - found it in the Tech Articles section. Thanks anyway. https://www.thirdgen.org/newdesign/t...ueswitch.shtml