I am trying to figure out the new M&H wiring harness that I bought for a v8 automatic 70 and my factory manual talks about a TCS relay and TCS SOL.

can anybody tell me what these parts and do I need them to start and run a rebuilt early 350.

thanks
jay

TCS stands for transmission controlled spark. It was an early emission control device, that was only used through 1973. If i had my haynes or chilton manual handy would tell you exactly what it did. It is not required on an early small block that is pre computerized, and the 80/81 models up did not have it anyway.

excellent reason for the factory service manual. description there along with lots of useful info.

You might do a search, there has been quite a bit of discussion on the TCS system.

Go here for some good info: http://home.comcast.net/~txss/TCS.HTM

Go here for some good info: http://home.comcast.net/~txss/TCS.HTM

I was hoping you would chime in
I couldn't remember who had that information. :o

It is not required on an early small block that is pre computerized, and the 80/81 models up did not have it anyway.


Except, of course, California....<sigh>

HEy Everyone:
I also found a description of the Transmission Controlled Spark Systems (TCS)with diagarams and pics at:
www.corvetteforum.net/c3/vette73/emission/tcs.htm
I have the same system on my 1972 Pontiac Catalina Convertible 455 w/ Turbo 400.
I am removing the TCS system. TCS is basically a not-too-effective emissions control, designed to keep engine very warm for less exhaust emissions at the cost of some fuel economy and performance. I could certainly do without more sensors and relays and solenoids and wires and a couple more pounds of weight on this baby. I am running the vac advance direct from the manifold and leaving the temp sensor for the temp gage on the dash just like on my 2 1966 GM's. 1972 is exempt from emission control inspections now anyway. If anyone wants any of my left over TCS parts (for cheap) just let me know.
Thanks, GatorGlenn (fordbuicksearay@yahoo.com)

Hey Everyone:
I also found a description of the Transmission Controlled Spark Systems (TCS)with diagarams and pics at:
www.corvetteforum.net/c3/vette73/emission/tcs.htm
I have the same system on my 1972 Pontiac Catalina Convertible 455 w/ Turbo 400.
I am removing the TCS system. TCS is basically a not-too-effective emissions control, designed to keep engine very warm for less exhaust emissions at the cost of some fuel economy and performance. I could certainly do without more sensors and relays and solenoids and wires and a couple more pounds of weight on this baby. I am running the vac advance direct from the manifold and leaving the temp sensor for the temp gage on the dash just like on my 2 1966 GM's. 1972 is exempt from emission control inspections now anyway. If anyone wants any of my left over TCS parts (for cheap) just let me know.
Thanks, GatorGlenn (fordbuicksearay@yahoo.com)

RE Hey Everyone:

The web address didn't post completely.
The missing section should read as follows:
/vette73/emission/

GatorGlenn