I've researched and found conflicting information, and didn't find the info on flowmaster's website.
Question 1: Are the American Thunder catbacks using the 40 series muffler or the 40 series delta flow?
Question 2: If AT catback is the regular 40 series, is the Force II system the delta flow or the 50 series mufflers?
I'm still confused about all this
Question 1: Are the American Thunder catbacks using the 40 series muffler or the 40 series delta flow?
Question 2: If AT catback is the regular 40 series, is the Force II system the delta flow or the 50 series mufflers?
I'm still confused about all this

