Does resistance matter in spark plug wires?

Resistance is the biggest buzzword when it comes to spark plug wires, but it usually comes at the cost of EMI and RFI suppression. And despite all the hoopla surrounding resistance, it will not typically make any difference in horsepower in an otherwise healthy and properly functioning motor.

Why do spark plug wires have so much resistance?

The resistance of many wires is measured in ohms per foot. Lower resistance means more of the ignition coils energy is going towards bridging the gap or the spark plug. That hotter spark can create a more even burn of the fuel/air mixture in the cylinder, and thus, more power output from the engine.

Does the length of a spark plug wire matter?

No, the length of sparkplug wire does not matter. However, The engine will not operate properly without the proper thread reach. If a spark plug with the wrong thread length is erroneously used, the piston or valve could strike it and damage the engine.

How many ohms should a MSD coil have?

This value will vary between coils, but a rule of thumb on MSD’s coils would be between . 03 – . 7 ohms. Secondary resistance is measured between the coil + terminal and the secondary tower (where the spark plug connects).

What can faulty spark plug wires cause?

Bad spark plug wires can interfere with the electrical current flowing to the engine, making it difficult for the engine to complete the combustion cycle. An incomplete combustion cycle can cause an engine to misfire, which means your car may jerk, stumble, or briefly lose power.

What happens if you use a shorter spark plug?

A spark plug that is too long can cause extensive damage to your engine while a short spark plug can cause poor gas mileage and spark plug fouling.

How do you check the resistance of a spark plug?

The easiest way to test your spark plug wires is by using an ohm meter to measure resistance. Look in the owner’s manual to find the appropriate resistance for the wires. Then, pull the boot off of the spark plug and unscrew one of the wires at the end.

What is the resistance of a spark plug?

Some internet research revealed that resistor spark plugs should have a resistance of between 4,000 and 6,500 ohms, and a check of the old Accel 576s resistor plugs revealed a resistance range of from 6,500 Ohms to 8,300 Ohms, with most in the 7,000 Ohm range.

What is ignition coil resistance?

Most ignition coils should have a primary resistance falling somewhere between 0.4 and 2 ohms; however, refer to your manufacturer’s specifications for the correct reading. If a reading of zero is displayed, that signifies that the ignition coil has shorted internally in the primary windings and needs to be replaced.