a lot also depends on what series of flowmaster is on the car,the 40 series are the loudest,the 30 series are quieter,a friend of mine just put on 40 series with an h-pipe and he's going to take them off because they are way to loud,they would be ok if he had left his cats on.if you are running an off road h-pipe,I would recomend the 30 series. nostang37791.5390277778
Posts: 1477
Joined: 6/10/2003 From: B'ham, WA Status: offline
Funny, everything I've read points to too much flow killing the low-rpm torque due to inefficient scavenging and the exhaust gasses cooling (and therefore slowing down) in the large diameter pipes. At higher rpms scavenging isn't all that much of an issue as the gasses are travelling at a much higher rate and the goal is to get them out and away (meaning smaller pipes or more obstructions hinder performance).
I've got mac headers, offroad h pipe and dual 40 series (with dual 2.5" out the back) and it sounds lovely. The neighbors might tend to disagree, but it makes me soil my shorts. :) I drove over 260 miles with the top down just listening to it the day I bought it.
My truck has hooker headers, no cats, Y pipe, single 30 series and single 3" out the back and it sounds nice, but too quiet for my taste.
Posts: 14
Joined: 6/23/2003 From: United States Status: offline
Alls I have to say is depends on how loud you want it to be... The lower the number the louder it is. My friends set up on his 01 GT is MAC O/R H-Pipe, and Flow 40's 2 chamber and man, its really loud for a GT. I plan to put on 2 chamber Flow 40's on the 01 cobra when I attain it.
Posts: 11
Joined: 7/4/2003 From: United States Status: offline
I've got Motorsport 1-5/8 headers to a catted Bassani x-pipe with 40-series 2-chamber flowmasters and 3" tips....it is THE best sounding mustang at WOT I've ever heard...I'm so proud of my baby! She's a beast!
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