[quote author=68MustangHCS link=board=1;threadid=1568;start=0#msg9464 date=1113337524]
I wonder what sized pipes would be best.
Can anyone explain how an exhaust system is put together?
For example if you have 2 1/2 exhaust inlets on your mufflers, would all over you pipes be 2 1/2 too or are the pipe ends stretched to fit the inlets on the mufflers?
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Myself, I prefer to get the factory pipe off the car. Most factory applications (even the pipes on my CS and GT) were 2" or 2.1/4" (really chokes a big block) so I replaced it with 2.1/2" pipes when I put my Flowmasters on. In order to get the muffler inlet and outlet pieces to fit, they simply use an expander to spread the end of the pipe going into and out of the muffler. I would of liked to use 3" but, on most older mustangs the rearend section (over the top) really causes a problem along with the gas tank. Creates a lot of crimping in the 3" pipe even if you try and custom make several different pieces, just don't have enough room to work the bends in the pipe. If you prefer to stay with 2" pipe and add Flowmaster mufflers they can simply add a section of pipe that expands from 2" to 2.1/2" to fit the inlet and outlet section of the mufflers. Your actually better off to just replace the whole system and go with 2.1/2" pipe (better exhaust flow). Hope this helps.
Don