Thermal Ignition Control Valves (TIC Valves)

[dardal@xxxxxxxxxxxxxxx]

I think what this valve does is the following.  For emissions purposes, they 
did not want the idle spark advance to be too high (high spark arvance causes 
high NOx).  However, too low vacuum advance makes the combustion more 
inefficient, and the exhaust temperature (and thus head temperature) will 
rise.  So, I think this valve is there to protect the engine if overheating 
occurs, by increasing vacuum advance and sacrificing emission calibration 
temporarily.  So, what I would do if I were you is try to find a way to adjust 
your vacuum advance at the most efficient setting for your engine (ie, the h*ll 
with NOx emissions) in which case the operation of this valve is irrelevant.  
May be you could incorporate a vacuum advance unit from an earlier car, if they 
fit your distributor.

D^2

Quoting Mark Blitman <markblitman@xxxxxxxxxxxxx>:

> hi gang:
> 
> can someone advise me on the merits,if any, of replacing this valve?
> this valve applies manifold vacuum to the vacuum advance unit of the
> distributor in order to increase engine idle speed and engine cooling
> when coolant temp.reaches above 225 degrees.Below 225 degrees it doesn't
> work.
> 
>