"Pre-cats are for cold start emission and heat up faster than the main cat. Letting the car idle about 3-5 minutes before driving is enough time to heat the main cat up."
Hey num nuts I just said that in my second post. What good does letting the car warm up do for you? Is is just sitting there why not just drive it to let it warm up. It will warm up alot faster that way plus you will be going somewhere not just sitting there wasting fuel. There was some study about this like 5 years ago I think.
"Not all cars use pre-cats. Just depends on the position of the main cat. I moved my cat forward more and used header wrap and I guarantee it lights off a lot quicker than it used to!"
That should work to be a very good setup congratulations. Do you hear many other people moving their cats up?? They donā??t because they donā??t know the advantages. I was strictly saying that gutting the precats is not the best thing to do from an environmental standpoint. If the SVT people are passing the cold start emission test with gutted precats in Cali. with flying colors then I am wrong and you guys win. I am not sure this is the case though. And why turn a light polluter into an average one anyways? Especially for small HP gains??
