I am purchasing Ford Racing wires for my 98 GT and was wondering what plugs are a good match, and I need to know what size I need (14mm?). Any wires better quality than Ford for around the same price?
use the oem recommended plug, unless your running a power adder. autolite double platinums are what i run. i think oem is just platinum. also dont try and run an exotic plug like a bosch +4, there crap plugs and really dont do anything. the double platinum plugs i run last longer, and be sure to gap them to the correct specs of .52-.56. they come .49 out of the box, and dont use those crappy round gauges theyre not accurate. invest in some good feeler gauges if you dont have any already.
I picked up some Bosch wires from Rock Auto pretty cheap (they were on warehouse closeout) and they are nice but they are not conveniently numbered like the Ford wires and the lengths are not as exact as the factory wires so some have a little extra length and some are a hair short so they don't route quite as nicely as the factory wires do, but functionally the appear to be equal.
The factory ignition stuff is pretty good so there's no real reason to stray to far from it unless you've got a good reason to, like extreme cylinder pressures from supercharging. I think the stock wires are 8mm and the FRPP wires are 9mm, right? That should be plenty.