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Discussion Starter #1
I really thought it was going to be crazy loud without the cat and muffler but it's not, compared to my old powerstroke.
Just the cool whistle out of the tailpipe but in the cab, I can't hear any major increase.
The best part is I bumped my MPG on the highway from 17.2 to 20.4, least that's what I show on the dash for consumption. I haven't reset the PCM yet by doing it old school (disconnect batteries for a while) and then gone on a drive.
I couldn't believe how big and heavy the stock muffler was and when the muffler dropped on the ground I asked my muffler guy if my truck just crapped a KIA!!
It's only been since Friday but I've shown a noticeable gain in seat of the pants power and better MPG's. Hoping to install a tuner to see more noticeable gains after I replace the restrictive turbo intake elbow.
 

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Did you increase the size of your pipe at all or did you just leave the the stock exhaust one minus the emissions crap
 

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Discussion Starter #3
I left the stock 3.5-inch pipe intact, just put in delete pipes for the muffler and converter.
The engine response is a heck of a lot better and since I don't plan on racing this pickup, stock pipe is find for my needs.
I wouldn't think 4-inch or bigger would make that much of a difference for me for towing and daily driving but then again, I think I'd need to throw some tunes on it.
 

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I really thought it was going to be crazy loud without the cat and muffler but it's not, compared to my old powerstroke.
Just the cool whistle out of the tailpipe but in the cab, I can't hear any major increase.
The best part is I bumped my MPG on the highway from 17.2 to 20.4, least that's what I show on the dash for consumption. I haven't reset the PCM yet by doing it old school (disconnect batteries for a while) and then gone on a drive.
I couldn't believe how big and heavy the stock muffler was and when the muffler dropped on the ground I asked my muffler guy if my truck just crapped a KIA!!
It's only been since Friday but I've shown a noticeable gain in seat of the pants power and better MPG's. Hoping to install a tuner to see more noticeable gains after I replace the restrictive turbo intake elbow.
That is why I was asking about the pipe size, I thought you were disappointed that it wasn't louder.

But yea a tuner will probably get you some more mileage
 

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I left the stock 3.5-inch pipe intact, just put in delete pipes for the muffler and converter.
The engine response is a heck of a lot better and since I don't plan on racing this pickup, stock pipe is find for my needs.
I wouldn't think 4-inch or bigger would make that much of a difference for me for towing and daily driving but then again, I think I'd need to throw some tunes on it.
Without the cat and muffler the stock exhaust flows well enough. A 4 or 5" doesnt help anymore than a free flowing stocker.
 

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I really thought it was going to be crazy loud without the cat and muffler but it's not, compared to my old powerstroke.
Just the cool whistle out of the tailpipe but in the cab, I can't hear any major increase.
The best part is I bumped my MPG on the highway from 17.2 to 20.4, least that's what I show on the dash for consumption. I haven't reset the PCM yet by doing it old school (disconnect batteries for a while) and then gone on a drive.
I couldn't believe how big and heavy the stock muffler was and when the muffler dropped on the ground I asked my muffler guy if my truck just crapped a KIA!!
It's only been since Friday but I've shown a noticeable gain in seat of the pants power and better MPG's. Hoping to install a tuner to see more noticeable gains after I replace the restrictive turbo intake elbow.
Can you post a video of the sound with the muffler and cat delete?
 

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I really thought it was going to be crazy loud without the cat and muffler but it's not, compared to my old powerstroke.
Just the cool whistle out of the tailpipe but in the cab, I can't hear any major increase.
The best part is I bumped my MPG on the highway from 17.2 to 20.4, least that's what I show on the dash for consumption. I haven't reset the PCM yet by doing it old school (disconnect batteries for a while) and then gone on a drive.
I couldn't believe how big and heavy the stock muffler was and when the muffler dropped on the ground I asked my muffler guy if my truck just crapped a KIA!!
It's only been since Friday but I've shown a noticeable gain in seat of the pants power and better MPG's. Hoping to install a tuner to see more noticeable gains after I replace the restrictive turbo intake elbow.
Is that all you did? Because i have my muffler deleted and i was wondering if i would be fine to delete the cat too?
 

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I did a home made cat delete 4" and 5" dpf back and without the resonator it sounds pretty good on my 2010 LMM
 

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Sorry,,,dpf back no muff
 

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