you "should" be running a colder plug, like copper or iridium (denso makes irridiums, ask silva bullit or whatever his username is)
i think that the zex kit is kinda crappy personally, i ripped mine apart, and made the solenoid button activation, and ran a 70 shot, and HOLY crap could i feel a kick when i hit the button, just used my afc to turn up the fuel
good luck, keep us posted
