for future reference Theres a place in brissie called Queensland Ignition Leads - they do custom ones in 9mm good quality cable very fairly priced. A complete set for my 302 V8 including fitting and cutting to size around the extractors was only $160!!

they also offer a 2 year warranty from memory

ON a side note - is it possible they damaged a spark plug? A friend of mine had a bent spark plug in his chev and it caused it to run like a dog as well...replaced it and away she went like new...