I need to fix a cracked flex on my downpipe, I thought about replacing the entire pipe to upgrade the cat and get a mild performance gain. I was going to order a ZZP downpipe but while reading through the reviews, I came across alot of people who all get a whistle when accelerating. Is it worth it to get a whole new downpipe, if so what is a good product...Or just remove the stock pipe and weld in a new flex? Is there really much of a gain with replacing the entire pipe?

 

the stock downpipe is one of the most restrictive parts (airflow wise) on the car. i would probably just get a new one. i have the zzp catless dp and its great, i love it. the only problem was that after about 3 weeks i threw an o2 code, but since im trifecta tuned i just had vince delete the code for me and i havent had any problems. the dp has been on my car for a good 4 months now i guess.