Need it as quiet as possible without choking the flow

[Tonyrodz]

dont think i have any videos of headers and all the 4" exhaust. no drone, a little loud accelerating. cruising was pretty quiet

couple inside vids with the turbo and all the 4". turbo didnt quiet it down as much as i thought it would. my phone picks up the sound a lot better than the gropro vids

and also make sure the headers and pipe dont hit the frame anywhere,

I LIKE IT!!

 

[Rocket Man]

dont think i have any videos of headers and all the 4" exhaust. no drone, a little loud accelerating. cruising was pretty quiet

couple inside vids with the turbo and all the 4". turbo didnt quiet it down as much as i thought it would. my phone picks up the sound a lot better than the gropro vids

and also make sure the headers and pipe dont hit the frame anywhere,

Frickin sweet!

 

[George Creswell]

I've been trying to decide which way to go with '13 Tahoe. I've already installed K&N Blackhawk CAI. Even with factory exhaust, it can get a little loud when you need some acceleration. I was looking at Borla before the pandemic hit, but that part is no longer available (???). I looked at Magnaflow, but didn't want the Sport series (too loud). Was told to look at Corsa or Stainless Works. I found a Flowmaster cat back set w/ dual exits, fair price, but haven't found anyone who's used it.

 

[FrankU]

rendeez That ***** scoots !!!!

 

[George B]

Just a thought/question. I know it's nice to switch from full flow to street-able sound levels but wont the change in back pressure affect the tune? I mean how much of a difference in power are we talking about for all the complication? Wouldn't a well balanced, good sounding system with a matching tune put down the smiles per mile numbers you seek without switching to open cutout mode? Are you going to have a different tune in the tow mode for open cutout vs closed cutout?

 

[Ilikemtb999]

Late to the party but a glass pack will certainly help kill noise. I’ve used the cheap summit ones on various cars for years. Currently only have 1 on my diesel blazer, exhaust exits in front of rear wheel and it’s 3” from the turbo. Was enough to make it tolerable to drive (it has zero insulation inside)

 

[iamdub]

dont think i have any videos of headers and all the 4" exhaust. no drone, a little loud accelerating. cruising was pretty quiet

couple inside vids with the turbo and all the 4". turbo didnt quiet it down as much as i thought it would. my phone picks up the sound a lot better than the gropro vids

and also make sure the headers and pipe dont hit the frame anywhere,

Love it.


Your description sounds like what I had before and what I'd like to aim for. I think I'm gonna nix the cat converter idea cuz I really doubt the exhaust temps are still around 800 degrees in the area I intended to put them.

 

[iamdub]

Just a thought/question. I know it's nice to switch from full flow to street-able sound levels but wont the change in back pressure affect the tune? I mean how much of a difference in power are we talking about for all the complication? Wouldn't a well balanced, good sounding system with a matching tune put down the smiles per mile numbers you seek without switching to open cutout mode? Are you going to have a different tune in the tow mode for open cutout vs closed cutout?

With how I'm planning on doing the exhaust, there will be very little difference in muffled or straight-piped. That's part of why I'm trying to avoid a turbo style muffler. Even if there was a difference that increased or decreased flow, it wouldn't be enough that the PCM couldn't account for. Really, what I have now and what it was tuned on is pretty much a straight pipe but with an 18" packed muffler about halfway down the line. It's just a straight-through pipe (other than the slight "S" to give it an offset outlet) with a perforated core wrapped in a couple inches of packing. I'm not doing the cutout for more power. Actually, I'd expect to lose a little low-end power with the cutout/straight pipe. I'm just doing it for the sound since I really liked the sound of the cam before I reconnected the exhaust. The cutout is so I could have that same unmuffled sound, but out the back instead of under the passenger seat. I didn't have the tuner change anything with the tow/haul setting. All it changes is the trans shifting and many have it altered to do things like completely remove Torque Management and speed up and firm up the shifts like a sport mode. I elected to try to keep my trans alive and am running the factory tow/haul programming. I had the normal trans tuning tweaked to take advantage of the engine mods and looser converter- higher shift RPM, faster, less sloppier shifts, downshifts instead of lugging, etc.

 

[George B]

With how I'm planning on doing the exhaust, there will be very little difference in muffled or straight-piped. That's part of why I'm trying to avoid a turbo style muffler. Even if there was a difference that increased or decreased flow, it wouldn't be enough that the PCM couldn't account for. Really, what I have now and what it was tuned on is pretty much a straight pipe but with an 18" packed muffler about halfway down the line. It's just a straight-through pipe (other than the slight "S" to give it an offset outlet) with a perforated core wrapped in a couple inches of packing. I'm not doing the cutout for more power. Actually, I'd expect to lose a little low-end power with the cutout/straight pipe. I'm just doing it for the sound since I really liked the sound of the cam before I reconnected the exhaust. The cutout is so I could have that same unmuffled sound, but out the back instead of under the passenger seat. I didn't have the tuner change anything with the tow/haul setting. All it changes is the trans shifting and many have it altered to do things like completely remove Torque Management and speed up and firm up the shifts like a sport mode. I elected to try to keep my trans alive and am running the factory tow/haul programming. I had the normal trans tuning tweaked to take advantage of the engine mods and looser converter- higher shift RPM, faster, less sloppier shifts, downshifts instead of lugging, etc.

Gotcha, it did sound freaking awesome so can understand your logic.

 

[iamdub]

Late to the party but a glass pack will certainly help kill noise. I’ve used the cheap summit ones on various cars for years. Currently only have 1 on my diesel blazer, exhaust exits in front of rear wheel and it’s 3” from the turbo. Was enough to make it tolerable to drive (it has zero insulation inside)

For the cheap, straight-through mufflers, the "glasspack" design is what I'm leaning towards. Really, my current muffler is technically a glasspack. It just has a lot more packing than the actual glasspacks have. It's a 5x8 oval, 18" long with a 3" pipe through the middle. All around it is fiberglass packing. The bullet/torpedo style ones like the "Cherry Bombs" are the same but with 1/2"-3/4" of packing. Mine was perfectly fine before but is just not sufficient for muffling without cats. I think if there was a 36" version of my muffler, it'd be what I'm looking for. Actually, I'm gonna see if they have a ~21"-22" version with center inlet and outlet. That'd give me about 40" of my current muffler...