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Discussion Starter #1
has anyone cut off their factory exhaust and looked into the inside to see how restrictive it looks ?

i have heard and read conflicting stories that the factory exhaust is fairly restrictive !
one story says it is the same as the V-8 F-150's in production and another says no they are fairly free flowing straight thru design.

i have an MBRP catback to put on but im not thrilled with the sound of it so i am debating on cutting off the factory muffler and welding it in place of the MBRP, this would give me the almost factory sound and still provide the stainless dual outlets for appearance until i find a suitable permanent stainless replacement

option 2 is put the MBRP on for the free flowing design and add one or even 2 resonators to the exhaust to quiet the tone back down.

i would like to have an idea of which route i want to take before sawing off the muffler and it is too sooty to shine a light into and tell what it looks like, its sorta like shining a flashlight into a black hole if you can imagine.
if i cant get an opinion to help me decide on whether i should use the factory muffler over or not i may just take the extra time and saw it off, nothing 20 minutes with a welder cant fix if i decide to reuse it.
 

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Discussion Starter #5 (Edited)
to clarify im almost positive my factory muffler is 3" there is a neckdown 2.5" from the Y-pipe into the stock resonator and then opens back up at the muffler inlet which is about 3' of piping and the muffler outlet is the same as the inlet.
my MBRP is a 3" for sure and opens up into dual 2-1/2" outlets


so by going with the replies so far it appears the factory design is straight thru but possible only 2-1/2"
i guess at this point the only positive answer is cut it open and see what it is without doubt.
i might just have to charge up my cordless sawzall tonight and give er hell tomorrow
 

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I did the 4" and 2 resonator route for a while. It still wasn't close to stock quietness in the cab. I probably dropped 20lbs swapping to my current setup. If you want deep and awesome sound til 4k rpm but fart city above that then go 4". Good luck with you're choice.
 

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Deep and awesome all the way through with Solo MR400 with Mach46 muffler added. Haven't added DP yet though.
 

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The factory exhaust is 2.5" from the y pipe through the resonator into the muffler then it's 3" from the outlet to tail pipe. I've measured.

Sent from my SM-N900V using Tapatalk
 

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Discussion Starter #9
you are right i just measured the OD on the muffler inlet and its 2-3/4" indicating a 2-1/2" pipe if not flared.
i think your setup with the super 10 is not bad in the cab but im wondering if i can get it even quieter.
 

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I just put solo off road dp on and had stock cat back altered at the muffler shop. They put a 3" flange and piping to the muffler. So its true 3" all the way. They even opened up the inlet on the factory muffler. Very very quiet with a little whistle. If you floor it it has a little growl. Its perfect for me. I tow a boat all summer. I like it so far.
 

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Discussion Starter #11
yea i tow alot during the summer and i have the duals out the back so i want to stay quiet.
 
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