the zex kit is intended for use on stock or midly modified engines so all your internals will hold up. it is necessary to retard ignition as stated on my zex installation manual; 55 - 0, 65 - 2, 75 - 4, but some ppl just use the rule; 1 degree per 25 shot.

just to be safe, don't spray in the lowest or highest gear, don't spray under 3k rpm, wait at least 10 mins between each spray, never spray past redline.

if i had an auto i'd floor it to Wide Open Throttle and let off a little before redline so it changes gears then push it back down to WOT.

my kit is new but so far everything is running smoothly, no overheating, no wierd noise or nothin.