Started, AFAIK, in Formula 1 by the Honda team in the 60's.  A bit crude.
Lay your hand on each exhaust pipe [one per cylinder] and the temp tells you
who's running rich/lean/etc.  A bunch more sophisticated since then.
Individual temp probes when setting up an engine and infrared readers at the
races, I think.  Drag racers do it as well, I know.

Mike

> From: Angus Gordon <agordon@BRIGHT.NET>
> Reply-To: Angus Gordon <agordon@BRIGHT.NET>
> Date: Wed, 2 Jan 2002 20:26:47 -0500
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: B. Bobs day at the dyno and the importance of fuel air ratio
> update
>
>   Mike Miller wrote:
>> Done all the time in racing though.
>
>
> Can you tell us more about how it's used?
>
> I'm a big fan of EGT gauges in airplanes, and of the Graphic Engine Monitor
> in particular but I don't see how it could be used to control the mixture,
> say through the ECU. As a diagnostic tool it'd be great. But I could buy a
> couple more Vanagons for the price of a GEM! :-)
>
>
> Angus
>
>
> ================================
> Angus Gordon                       '89 Carat
> NW Ohio                            '86 Syncro
>