Does Spark plug wire length significantly effect the voltage going to the spark plug?

Question

I bought universal MSD Spiral Core Street Fire spark plug wires the other day. Some of the wires are pretty long and i just wanted to see if the length would cause a loss in voltage? If the length does effect voltage should i cut the wires to make them shorter in length?

Answer 1

YOU SHOULD NEVER CUT SPARK PLUG WIRES THEY USUALLY COME IN DIFFERENT SIZES FOR A REASON THE BEST WAY TO REPLACE THEM IS TO TAKE ONE WIRE OFF AT A TIME THEN MEASURE IT WITH THE NEW ONE AND WHICH EVER IS CLOSEST TO THE SIZE OF THE ORIGINAL ONE INSTALL IT IN THE PLACE OF THE OLD ONE

Answer 2

There is NO difference!  Neither the length nor the size of the plug wire really matter.  The longer the length the greater the resistance and the higher the voltage the coil needs to supply power to the spark plug, so it burns just slightly hotter.

Answer 3

You can't just cut spark plug wires, whatever length you bought them at you are stuck with.

It doesn't matter that much unless you are trying to keep your engine bay looking nice in which case you should have got some application specific wires.

Answer 4

There is a direct relation to the length and the size of the wire to how much resistance it has. The fact is though that with the application that you are talking about the results are negligible. You can cut them too but I don't recommend that you do that. They are a lot of trouble if you do. It is hard to get a good seal and the water repelling action is compromised

Answer 5

As long as your coil is capable of putting out the voltage needed, it won't be a problem. It will supply whatever voltage is necessary to get to ground. A longer wire will require more voltage, but not that much. The spark plug gap requires more than the longest plug wire. If you want to cut them shorter simply for appearance sake, that certainly can be done, but you have to be good at stripping wires. Just cut it a little longer than you want it, strip off about 1/2 inch of insulation on the end you're shortening, bend the filament over to the side so the terminal will clamp down on it, and spray the boot with some silicone spray to slip it on. (practice with your old ones first) New terminals are easier, but you can get by with re-using the old ones if you're careful taking them off.