Darn it. I already bought the BR10ECS plugs because I went by the manual, which I guess was not updated. Will it have any negative effect? I'm more interested in reliability and not having major engine problems as opposed to squeezing every ounce of performance. If it's going to cause me grief I guess I'll have to scrap them and buy the BR9ECS. I've tried to get a clear explanation of the difference between the two but had no luck so far. I know that some are called hotter or colder plugs, but I don't understand what that means in practical terms. Thanks for any advice guys.