what is the difference between the ngk tr 5's and the 55's? and what mm wire should i use?

 

Not sure what the difference is between the plugs, but from what I understand, a stock Z or TA should go with the TR55 or TR55-IX (Iridium) plugs, gapped at .050

I currently have the TR55-IX with the Magnecore 8.5MM wires on mine, and they're very high quality, and helped out the engine smoothness a lot over the plats I had in there when I bought the car (bought it used, think they were ACdelco plats in there when I bought them, and crappy ones at that)

At any rate, the TR55, or TR55-IX would be the way to go if you're mostly stock...if you get a blower, most ppl will say go with the TR6 (temp is one step lower than stock)

 

I just bought a set of NGK TR55 and a set of MSD's 8.5 mm Super Conductor Wire sets. I will be installing them next weekend, I can post a reply telling you how it turns out.