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sierra 8.1 exhaust

yukon25008.1

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yukon25008.1 Senior Enthusiast

yukon25008.1

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My question is the truck has 3" from the factory all the way back into a single tailpipe.. So honestly the 3" is overkill for the stock power it makes. So im debating on the exjhaust layout. and in the near future going to get a set of stainless works long tubes, after that the cats are gone, and im gonna have a 3" in and out X-pipe to help with backpressure. then 2 borla mufflers, and im going with two tailpipes out. My question is if i go with 2.5 tailpipes out after the mufflers, so is it gonna hurt me or help.. with the whole system being 3" and then just 4-6' of tailpipe being 2.5" im thinking it will be fine..and if anything help with backpreesure/TQ.

Please let me know what you guys think, Thanks

 

By the way i just did a raylar cam, not tuned yet. and i will be getting the long tubes, and eventually the raylar heads..So all said and done ill be around 500 HP at the crank

yukon25008.1 Senior Enthusiast

yukon25008.1

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I removed and emptied the cats yesterday, and had my freinds shop weld the back in place, it seems to run better, sound good, Im really waiting on the tune so i can really see and feel the difference,

yukon25008.1 Senior Enthusiast

yukon25008.1

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Really..no one has an opinion..

Has anyone ever used one of those universal tailpipe kits

Prokopchuk_9 Senior Enthusiast

Prokopchuk_9

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Man...x pipe is a waste of money in my opinion...but if that's what you want okay. I run 3" all the way from the cats, dual in single 4" out to tail pipe with 5" tip...sounds beautiful. I think what you want would be good, but I would go with 3"...you'll still have all the back pressure in the world. The only real advice I can give ya is use 309 stainless, don't fall for the stainless coated marketing scheme. Get the real deal. Post a sound clip when ur done, borlas sound nice. Magnaflow has always been my favorite...

Prokopchuk_9 Senior Enthusiast

Prokopchuk_9

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And ya with a good set of heads, headers and cam...I would be seriously looking into the 3" exhaust...especially at 500hp. Long tube headers too. I wanna hear this thing when it's done!!!

yukon25008.1 Senior Enthusiast

yukon25008.1

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Thanks for your reply, i had two borla 12" 3" in/out on an 05 sierra 6.0 w/ cats and it sounded great.

The reason for the X was just to keep up a little backpressure with the cats gone, And help with scavagning...which i dont completely understand yet, but ill find a shop that can bend 3"

I just dont want to go back to a single 3" tailpipe.. Although dual 3" in and single 4" out sounds good!

I have a magnaflow on my 5.7 van daul in 3" dual 3" out and it sounds good, Id really like to just have a mild rumble at lower rpm,s and a nice loud sound when into it... what im concerned with with the 12" muffler vs the 16" is the sound inside the cab at 2-3000 rpm,, Im just thinking of pulling the camper with the kids sleeping in the truck..I dont want it that loud that its annoying.. That was also a reason for the X-pipe

Mckenzie Senior Enthusiast

Mckenzie

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i got nothing but true dualed straights after the cats and it sounds pretty dam good, your 8.1 would sound like a beast true dualed with no mufflers

Prokopchuk_9 Senior Enthusiast

Prokopchuk_9

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I have the cats knocked outta mine as well, downstream 02's shut off. I'm tellin ya man, a friend of mine added a x-pipe under his truck. He got it for free, now I know why someone gave it to him. Didn't make a difference, sounded identical, felt the same everything man. Waste of cash IMO, others may differ. But my personal experience it was a waste of time, an exhaust shop will tell you different tho...only because they are tryin to sell you shit. The Magnaflow I'm running is 22"....it sounds amazing. Although it does resonate At about 1700-2100 rpm on the highway, it's not that bad tho. I have a little one as well, when she was just a baby she would stil sleep...it's nothing major. Even the wife doesn't complain... Worth it IMO, Magnaflow or corsa just seems to be the best build quality...I wish I had a sound clip of my truck...

yukon25008.1 Senior Enthusiast

yukon25008.1

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I cant wait to get the exhaust finished.. but right now the fuc... truck wont even start..

hit the key and nothing.. not sure if its the ignition switch,

Anyway, the only reason i planned on using the x-pipe was because of the cats being gone .. it made sense that the X would help with some back pressure/torque, but im sure it will sound good.

Im debating on the corsa,.. thats one brand ive never tried. How does it compare to borla and magnaflow?

Prokopchuk_9 Senior Enthusiast

Prokopchuk_9

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Man, borla is usually more expensive and IMO its not up to par in quality/sound compared to Magnaflow...I've never owned borla so I can't comment but I've heard it on a 5.3 sounded okay...not as grumbly and deep as Magnaflow tho. Fit and finish looked okay tho. But I do know his price was more expensive than the comparable Magnaflow system. I've owned cherry bomb (I know lol), flowmaster, mbrp and Magnaflow. Now I won't buy anything but Magnaflow, sounds the best, lasts the longest best over all package I think. Corsa sport is supposed to be nice as well, steel baffles=no drone. But it's $$$$$ as well...look up some YouTube vids dude.

  • 2 weeks later...
yukon25008.1 Senior Enthusiast

yukon25008.1

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Im not really leaning towards flowmaster..but there 50 series big block muffler looks good, anyone use it?

  • 2 weeks later...
yukon25008.1 Senior Enthusiast

yukon25008.1

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I thank everyone for reading this post, If you dont mind reading my exhaust post in the 'engine/powertrain' area and let me know what you think... I need to get this exhaust complete..

Thanks

kurt1993 Enthusiast

kurt1993

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i just put a dynomax catback on its the stock size 2 into 1 from the 1 on its 4" with a 5" tip im happy with it..i just want a tune now

yukon25008.1 Senior Enthusiast

yukon25008.1

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you will love the tune, I would go in person... then get the autocal to adjust

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