Two Straight Pipe Sections

spinsall4 · 07-07-2011, 12:11 PM

Does anyone have a clear picture of a system with the factory crossover resonator section and factory unmonitored cat section removed entirely. basically running straight pipes through those two sections. Would be interested in sound, performance, etc. opinions

BTM · 07-07-2011, 02:17 PM

While not exactly what you're looking for, I just got done gutting my secondary cats yesterday (props to wassup61 as always). Other than that my exhaust is totally stock. It sounds just like stock, but louder, maybe a little less rasp, no drone - not at all annoying. I've only put about 25mi on since, but it does seem to rev a little freer in the mid range. Definitely a PITA though.

spinsall4 · 07-07-2011, 03:39 PM

Dont suppose you have a quick picture with the cats off? I have a great exhaust guy and was thinking of having him build me one continuous piece that replaced both the cats and crossover sections. Complicated bends but he is crazy talented. He builds custom headers and exhaust systems for street rods so this is a snap for him. Just wanted to hear from some other folks before I asked him to spend the time on it.

BTM · 07-07-2011, 03:58 PM

Sorry no pics, but it didn't appear to be all that complicated. Just to be clear, I didn't cut the cats out, but gutted the honeycomb, leaving the pipes themselves intact. So it's sort of like they are now just resonators. Straight pipes in place of the cats would probably be louder.

07-07-2011, 12:11 PM	#1
spinsall4 Private 2 Rep 61 Posts Drives: SB 07 MZ4 Coupe Join Date: Feb 2011 Location: Nor Cal iTrader: (0)	Two Straight Pipe Sections Does anyone have a clear picture of a system with the factory crossover resonator section and factory unmonitored cat section removed entirely. basically running straight pipes through those two sections. Would be interested in sound, performance, etc. opinions
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07-07-2011, 02:17 PM	#2
BTM Banned 483 Rep 10,309 Posts Drives: A///MERICAN!!! Join Date: Mar 2010 Location: A///MERICA!!! iTrader: (11) Garage List 2007 BMW Z4 M Coupe [7.20]	While not exactly what you're looking for, I just got done gutting my secondary cats yesterday (props to wassup61 as always). Other than that my exhaust is totally stock. It sounds just like stock, but louder, maybe a little less rasp, no drone - not at all annoying. I've only put about 25mi on since, but it does seem to rev a little freer in the mid range. Definitely a PITA though.
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07-07-2011, 03:39 PM	#3
spinsall4 Private 2 Rep 61 Posts Drives: SB 07 MZ4 Coupe Join Date: Feb 2011 Location: Nor Cal iTrader: (0)	Dont suppose you have a quick picture with the cats off? I have a great exhaust guy and was thinking of having him build me one continuous piece that replaced both the cats and crossover sections. Complicated bends but he is crazy talented. He builds custom headers and exhaust systems for street rods so this is a snap for him. Just wanted to hear from some other folks before I asked him to spend the time on it.
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07-07-2011, 03:58 PM	#4
BTM Banned 483 Rep 10,309 Posts Drives: A///MERICAN!!! Join Date: Mar 2010 Location: A///MERICA!!! iTrader: (11) Garage List 2007 BMW Z4 M Coupe [7.20]	Sorry no pics, but it didn't appear to be all that complicated. Just to be clear, I didn't cut the cats out, but gutted the honeycomb, leaving the pipes themselves intact. So it's sort of like they are now just resonators. Straight pipes in place of the cats would probably be louder.
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