> I have been wondering about the same thing {The purpose of the electric 
> fan for the heating}

 I don't have a fan in my '71 but it would be nice to have when the engine's
idling. I think the electric fan is supposed to boost the airflow at low revs.

> 						   ... What happens is I'll 
> be driving along the freeway at night, flat out and all of a sudden the 
> engine starts to lose power and seems to sputter/miss with little 
> backfires...
> filter, replaced the plugs and hade the timing set. I can't think what 
> else it could be, except maybe the carbs? Any help would be greatly 
> appreciated!

 Hmm, I have had similar symptoms. I used to get misfiring when my ignition
timing drifted because of a flakey valve, it generally happened when the engine
was hot.
 I'd check the compression, anyway. Also, intermittant/often-when-hot problems
are often related to ignition parts fading out. Try a new condenser and swap in
a new coil if that doesn't help. HT is funny stuff.

Cheers,
        W.
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