I've blown 2 coil packs within an hour on an '83 GMC Suburban 350 engine. What...

[Christopher]

...might the problem be? I recently had a cam replaced on my truck. Driving it home from the shop, the engine just stopped. We eliminated fuel issues, arrived at a blown coil pack, and replaced it. It turned over, ran for about three seconds, and stopped again. What could possibly be causing the issue?

 

[Kenny D]

Are you sure the coil is bad? Did you test it? I suspect your problem might be a bad coil resistor or arc seal gasket under the coil. More often than not, rather than a bad coil, a bad coil resistor or arc seal gasket will be the source of the no-spark condition on the GM HEI coil-in-cap distributors. It is inexpensive, easy to replace, and looks like this:
http://info.rockauto.com/getimage/getimage.php?imagekey=938744&imageurl=http%3A//info.rockauto.com/Airtex/6R1000.jpg

But a no-spark condition on the GM HEI distributors is by far most often caused by a bad magnetic ignition pickup in the distributor.

Here is a link that will help you test the coil (scroll down to distributor components testing):
http://www.angelfire.com/realm2/84camaro/fix_the_car/coil/coil2.htm

 

[Serial Stunter]

A short to power in the charge circuit of a coil pack can over-heat it in less than 20 seconds. Who's been messing with your wireing harness????