My Mx5 was firing right out of the blue. At low revs and just a bit hesitant. Pondered what it could be and though as I've had it for 5 years and they are ment to go through HT leads I try a new set of these first. So off I went ot MX5parts and brought some. The blurp by them:
High Performance 8mm ignition lead set.
Ignition leads are essential to the life of your MX-5. Automobile manufacturers incorporate three ignition wire technologies in their vehicles, either resistor wire leads with wire-wound resistors in the cable, carbon suppressed wire, or ignition wire with copper core where the suppression resistor is incorporated within the connectors. Faulty ignition wires can damage catalystic converters. Therefore when replacing wires you should always replace them with a quality wire set. This quality wire set guarantees ignition cycle precision, optimum engine performance and low fuel consumption - reflecting the quality of original equipment. These wires are made to our specification and utilize Beru connectors because they are the finest available. 40,000 volts, temperatures up to 500 deg.F, vibrations, salt water, road dust, cleaning agents……these are just a few of the continuous demands to which connectors are subject day-in , day-out.
Well they arn't the right length which if I'd bothered to read the reviews I would have noted and got a different set. How nice they look in yellow, and this was the best I could route them. On the plus side the car purrs now.....