[turtlefeeder]

hey guys I got an issue and need your help/experience!!

so I recently upgrade to a mxp sp exhaust from ft86speedfactory and it was good for the first day didn't really go on freeway or long drive, a few days last week it started making a knocking noise after a drive on the freeway/highway from work, I came to an exit and notice a loud knocking noise decending from loud (can hear with music on) to soft (like popping from hot manifold/header) than it dissappear and all this was under like 20second. now I notice it anytime. I've contacted ft86speedfactory and they said it may be a leak and ask me to check my bolts if they're tighten and connect correctly. so I jacked the car and went under.. didn't see issue or couldn't find one. so I took it to my uncles shop, he put it on in a lift and visually inspect, told me it's correctly installed ,even tried to tighten the bolts more but it didnt budge, he also said it's new and need some time to settle (if it's true it needs time let me know) but have you guy got this problem or can think of something else I might of missed?

thanks in advance