I`ll explain a few things, for some it`s kind of hard to take in but it`s really simple. Lets start with the basics, electricity is like water, it`s smart, but lazy. It will always take the path of least resistance. Now, with that out of the way, lets get into plug wires. Cheapy parts store wires have solid cores, these work fine for daily drivers, but even for that role I don`t use them.
Solid core wires have high resistance, now think back on smart and lazy, path of least resistance. if There`s a high amount of resistance in the plug wire and the spark can find a easier path it`s sure going to take it and this can cause many problems in a high performance engine such as cross fire detonation which is the worst kind. Now we look at spiral core spark plug wires, these have considerably less resistance, some get down to some pretty low levels, I mostly use Moroso blue max 875 ohm spiral core wires. You pay more for them, but they last far longer than solid core wires plus do a much better job. Now, on to looming the wires. If the wires are crossed up, and it doesn`t matter which type of wires you use this can cause cross firing and we already know what damage that can do. Back in the early days Smokey Yunick didn`t pay any attention to the routing of plug wires, then he decided to do a experiment. He connected up 8 plug wires to a machine, and laid them over a metal work bench, then shut the lights off so it was completely dark. What he saw he said he`d never forget, the wires were lighting up from the electrical energy leaking around them and they were arcing fire everywhere creating all kinds of cross fires. Afterwards it taught him to pay very close attention to the routing of the spark plug wires. However, I think that was in the days before they had spiral core wires avalible and with there lower resistance aren`t as prone to doing so, but I still recommend to others take your time and route them correctly and away from each other. No, it won`t give you anymore horsepower, but it could save your engine especially when you consider the problem on the small block chevrolet, 1 8 4 3 6 5 7 2 As you see, 5 and 7 fire one behind the other plus they are side by side, if 5 arcs 7, and 7 has just filled the cylinder with air fuel mixture and the piston is at bottom dead center about to start it`s way up and a cross fire arc sets the charge off in 7 bad things happen as the combustion hits it with the piston half way up the cylinder which combustion makes it want to go back down but it can`t. Now you know more useless information.