Re: free-flow exhaust question
Be warned removeing exhaust system parts or using to large a exhaust pipe WILL result in insufficient back pressure. Which WILL cause the valves to burn and leak.
Exhaust modes are a good way to increase preformence and do sound cool. But if you take it to far it will hurt your engine. As to your removing exhaust pipe from the cat back. The Cat may produce enough back pressure to prevent damage (don't know for sure).