removing muffler
New User
Joined: Apr 2002
Posts: 11
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From: Salt Lake City USA
removing muffler
A guy I used to work with had a local mufler shop remove the muffler and bend up a 3" pipe to replace it and the tail pipes on a 95 F350 With 460. I never got a chance to hear it before he traded it in but he said it sounded good (not too loud with the cat still in place) and had more power. Has any one done this? I Have a 97 and around $70 to do this sounds a lot better to me than a couple hundred for a cat back system.
Senior User
Joined: Jun 2000
Posts: 491
Likes: 0
removing muffler
On my 92' F-250 351w, I ordered a stainless steel cat-back system from gibson. paid $44? for it. When I installed it I gained 10hp at high rpm (not peak) and 14ftlbs at high rpm. SO the cat-back with muffler helped me at 4000rpm. When I got through dynoing it I drove it for a while until I got tired of listening to a Z-71 instead of my own truck at a stop light.
I took out the muffler a replaced it with a 3" pipe. So I now have 3" mandrel bent piping from the cat, back. Sounds louder but still quiter than your average Z-71. Have resonance at 2,000RPM but I had that with the muffler in also. Have to figure a little more power, but not much. (You could drop a tenis ball through that muffler.)
With the set up I have now (just piping) you get a burble when down shifting. Lovely rumble at idle (shakes windows, but not "loud", like it's out of the hearing range or something). You don't notice it in the cab with the windows up and the radio on. Change either and you'll hear it in the background. I have a 351w with 8.8:1 compression. Should sound much sweeter on a 460. In fact, if you do this, let us know how it sounds, might do it to my car.
Plus, much cheaper.
I took out the muffler a replaced it with a 3" pipe. So I now have 3" mandrel bent piping from the cat, back. Sounds louder but still quiter than your average Z-71. Have resonance at 2,000RPM but I had that with the muffler in also. Have to figure a little more power, but not much. (You could drop a tenis ball through that muffler.)
With the set up I have now (just piping) you get a burble when down shifting. Lovely rumble at idle (shakes windows, but not "loud", like it's out of the hearing range or something). You don't notice it in the cab with the windows up and the radio on. Change either and you'll hear it in the background. I have a 351w with 8.8:1 compression. Should sound much sweeter on a 460. In fact, if you do this, let us know how it sounds, might do it to my car.
Plus, much cheaper.
Elder User
Joined: May 2001
Posts: 760
Likes: 0
From: Billings, MT
removing muffler
I just did this a few weeks ago to my '89 F-250HD 4x4 460. I got under, took off the stock muffler and got simple. The pipe out of my cat is 2.5", so I picked up a 2.5" 45 degree elbow and a 2' 2.5" pipe and clamped it on, and now my pipe exits in front of my passenger side tire instead of behind. For results, I seem to have lost a VERY minute amount of low end torque, but picked up some horses above 2500. I also went from an average of 8.7 mpg to 9.3. As to sound, it's about the same as stock at idle, but it has a low rumble between 1200 and 2000. Past that it has a funky hum that's almost a howl. I really have no complaints, and for about 8 bucks I got a better sound, a smidgen more power, and a pretty nice increase in fuel economy.
The Law
The Law
Senior User
Joined: Jun 2000
Posts: 491
Likes: 0
removing muffler
:-X11 I seemed to lose some low end torque also.
>I just did this a few weeks ago to my '89 F-250HD 4x4 460.
>I got under, took off the stock muffler and got simple. The
>pipe out of my cat is 2.5", so I picked up a 2.5" 45 degree
>elbow and a 2' 2.5" pipe and clamped it on, and now my pipe
>exits in front of my passenger side tire instead of behind.
>For results, I seem to have lost a VERY minute amount of low
>end torque, but picked up some horses above 2500. I also
>went from an average of 8.7 mpg to 9.3. As to sound, it's
>about the same as stock at idle, but it has a low rumble
>between 1200 and 2000. Past that it has a funky hum that's
>almost a howl. I really have no complaints, and for about 8
>bucks I got a better sound, a smidgen more power, and a
>pretty nice increase in fuel economy.
>
>The Law
>I just did this a few weeks ago to my '89 F-250HD 4x4 460.
>I got under, took off the stock muffler and got simple. The
>pipe out of my cat is 2.5", so I picked up a 2.5" 45 degree
>elbow and a 2' 2.5" pipe and clamped it on, and now my pipe
>exits in front of my passenger side tire instead of behind.
>For results, I seem to have lost a VERY minute amount of low
>end torque, but picked up some horses above 2500. I also
>went from an average of 8.7 mpg to 9.3. As to sound, it's
>about the same as stock at idle, but it has a low rumble
>between 1200 and 2000. Past that it has a funky hum that's
>almost a howl. I really have no complaints, and for about 8
>bucks I got a better sound, a smidgen more power, and a
>pretty nice increase in fuel economy.
>
>The Law
