I recently posted a thread about exhaust advice. I'm new and confused to the Mustang 4.6 v8 world, but proud to involved now. My situation is that i disliked the silent noise the stock exhaust had, so I had added flowmaster 40 mufflers to the stock exhaust system. The sound is definitely better and deeper, but the car seems to have a restrictive type of feeling. Everybody is telling me to add a midpipe to solve that problem, either a x or h. Doesn't the car already come with an h midpipe, but since it's stock does that make the exhaust restrictive with the flows. Or do I need a the 2.5 tubes verses the stock 2.25 tubes? Do I just need to add a complete catback system? Some people say I need headers and long tubes. I really just want the car to run like it did originally with the stock exhaust system, but with that v8 rumble. What do I need really need to do with the flomaster 40 mufflers? Aftermarket h pipe, xpipe, complete catback, or the 2.5 tube thing?

 

i had stock exhaust with flowmasters welded inplace of the stock mufflers. i just got done installing my off road h pipe about an hour ago, and it sounds awesome, its got a nice rumble to it, its louder, but not obnoxious. tomorrow im gunna take her for a test drive to see how she sounds at speed

 

get an o/r h pipe....you'll be shocked at how much better/meaner/louder it will sound.....the ponies you'll pick up are a plus too...its a noticable gain!!

 

The stock exhaust is more restricted because of the catalytic converters. Get an off road or high flow catted mid pipe for a replacement (prefereably off road if emissions aren't an issue). You'll behappy either way.

 

the stock mid pipe has 4 cats go with at catted H or X which has two cats or just go o/r which has no cats and is the least restrictive... but if you have the money you should just do everything LT's mid pipe and cat back.