I've installed a MSD 6T ignition as well as blaster coil on my XJ. I've been running a .050 gap and I eat through the regular champion plugs like no tomorrow. I did just find out that Champion makes a platinum plug for around $2 each. I just purchased these last night and I'm going to put them in this weekend. Unlike some of the other low cost platinum plugs, it's not a platinum bead on the end of the electrode. I like the ability to run a larger gap and some of the other platinum come pre-gapped and you can't change it. Hopefully these will last longer.