i just replaced my spark plugs and wires. ford 9mm and yes those terrible denso iridiums. they work great by the way. the engine runs smoother and doesnt stumble at a cold start up as it used to. as far as extra power i dont know maybe a little but i got a crazy deal on them. my last plugs were pretty nasty. i also have a cold air intake w/k&n filter and custom cat-back exaust which brings me to my point. the engine sounds different, it is a smoother but just plain different sound AND my exaust is not as loud. i can tell up to around 3500-4000 when the intake is louder inside than the exaust. does any one have any idea why!?
