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Chicken Converter

I finally got around to wiring up my 'lockup' torque converter in the Firebird... except for 2 more pieces I need to make the vacuum switch work.

The lockup function on an automatic transmission is supposed to save on fuel mileage and keep the transmission running cooler. It basically provides a direct connection between the engine and transmission. In normal operation there is generally a little slippage (like if you have a standard trans and your foot is partway on the clutch pedal, but not quite as significant).

Anyway, the car came with an old 2speed automatic. That was soon upgraded to a 3spd, and now to a 4spd with Overdrive... a must with today's fuel prices.

The problem with the lockup converter is it has to know when to unlock, otherwise you can end up with shuddering and a host of other problems. Since I dont have a computer to tell it when to unlock, I had to hook it through a couple of switches. I also am using a manual switch with an LED light to tell me if it is working correctly, and to manually disable it if I need to. I might eventually eliminate this switch, but it looks kinda cool all lit up ;)

One switch is on the brake pedal. I'm using a 'cruise control' brake light switch because it has 2 connectors, one normally open, the other normally closed. This will unlock the converter when I apply the brakes.

The other switch I don't have hooked up yet. I need to get a couple pieces from the GM dealer. This switch is vacuum operated, and theoretically will only let the lockup function work while at cruising speed, automatically unlocking when vacuum drops, such as when the engine is under load (going uphill, or heavy right foot).

So, here's the pics. First pic is all the pieces i'm using, minus all the wire, hose, and connectors between. Then I have some 'as installed' pics. You can see a blue wire wrapped around the vacuum switch on the fender. Once I get the connector, I'll splice into that. I also need a delay valve in the hose leading from the carburetor.