BTW unless you are making 400hp, I do not recomend putting BPR7ES spark plugs in. I always ran slower with them when I had the 16G and they fouled to much. BPR6ES is just fine for a 300hp or less car.

Colder plugs DO NOT increase spark or power, all they do is cool off faster which can help a bit if you have alot of knock or are tunning on the edge. Because they stay cooler they may not burn all the deposits off causing them to foul and you will then LOSE power.

If you have less than 400hp and are knocking alot fix your problem, lower your timming or increase fuel, plugs aren't a mod.