Information on mid pipe
 

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I was snooping around my mustang today. It’s a 2005 Mustang GT with as far as I know just SLP loudmouths axel back. But I noticed something funky. Looks to me like someone cut and welded a little x pipe into the stock mid pipe. Would I have any issues swapping mid pipes out in the future? Looking into either off road x or a hi flow catted x. Also, is a hi flow cat worth it for overall loudness? I’m concerned that a off road set up would be overbearingly loud but I don’t wanna waste money on a hi flow cat setup if it won’t do much.

Since your over the axle/tail pipes have been cut shorter in order to splice and weld in the X crossover, chances are, the over the axle pipes are going to be a bit too short for an off-road or high-flow catted X to fit properly. It will also depend on whether any section of the stock catted mid-pipe was also cut to make room to weld in the X crossover. Needless to say, I pretty much went thru the same situation and ended up having to purchase new over the axle/tail pipes in order for everything to fit and line up properly.