318 Spark Plug Gap?

I once had an 80 firebird esprit with the gutless and nutless buick V6 with factory HEI and superlight hydramatic three speed. I don't know what was different in the ignition to that particular engine but the spark plug gap spec was an .120 or .125 inch gap. I know, a full eighth inch! I don't think top fuelers use that much gap, and their mag systems have the output of an arc welder. Had factory high voltage warning stickers anywhere near the distributor. The only thing that could have helped that car was a good early seventies 350 Olds engine.