I find it surprising that one would expect to "feel" a difference just by changing plug wires? Get real, horse power doesn't come that easy. I run magnicores on my SRT for simply for the common sence of it all. When your pushing over 400hp out of a six you can't but improve spark/performance with large guage wire. It's why you can't cut corners and obtain h/p. When you have done all the major modifications that cost $$$, then throw in a set of 8.5mm wires but until then save your change.