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Old 03-24-2002, 09:09 PM   #1
jason7627
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Question tcs switch?

Gettin my '72 ready for the 454 and found a set of wires for what my wiring diagram calls a tcs switch.It shows a tcs switch and tcs solenoid, but they are no longer there, just the wiring. 3 questions. 1) What does it do? 2) Can I get rid of it. 3) If I can't get rid of it anyone know where I can get parts for it?

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Old 03-25-2002, 12:19 AM   #2
71Chev
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I think it is transmission controled spark or something close to it.
Not exactly sure what it does.
Mine isn't hooked up and it runs fine, so I don't think ya need it.

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Old 03-25-2002, 12:20 AM   #3
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TTT
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Old 03-25-2002, 07:58 AM   #4
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Search and you will find.

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Old 03-25-2002, 08:27 AM   #5
JimKshortstep4x4
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The TCS switch controls the vacuum going to your vacuum advance on your distributor. It allows vacuum to the vacuum advance under two conditions: 1) The engine temperature at normal, 2) The transmission is in high gear. It basically keeps the timing retarded as far as the vacuum advance goes when the engine is cold or when the transmission is in the lower gears. The prevailing theory at the time for emissions was to retard timing to cause the manifolds/exhaust to get hotter, therefore burning the emissions.

The effects on performance and gas mileage were pretty detrimental. I have always suspected that the net effect of the TCS setup was to increase emissions overall, but I have never seen any studies.

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Old 03-25-2002, 11:14 AM   #6
Fast68Chevy
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easy fix is to just run the advance hose straight formt he distributor advance diapragm to the carb base, there, done...

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Old 03-25-2002, 09:51 PM   #7
jason7627
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Thanks, looks like its out of here.
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