6.2 Exhaust, What do you have?

[KARNUT]

I decided to take a chance yesterday and I pulled the muffler. The ONLY thing I did was pull the muffler, and inserted a stick of 3" pipe. I have a late 6.2L, so the piping is all 3.5", but shops around here don't carry that. Besides, the muffler and the flapper are both 3"...so why the larger pipe? I don't get it, but oh well. Again, I left EVERYTHING else including the flapper.

 

Here's my impression.

• First, hands down this is THE cheapest way to get a little noise, period. ~$40 and you're good to go. If you're considering a $1,200 exhaust...seriously try this first.
• NO DRONE AT ALL. Zero. Zilch. Nadda. I only have about 75 miles on it, but I never detected even the slightest hint of drone. Windows up/down, any speed, any load, you name it.
• At cruise and idle it's juuuuuust a tad louder than stock. At 70 on the highway, cruise, no radio, I would never have guessed that anything had been touched. I very seriously doubt anyone would assume otherwise as I'm quite familiar with the sound and I wouldn't have noticed unless I already knew and was listening for it. At idle, by the pipe, it's a little more throaty. But even my exhaust dude was almost confused since it still sounded stock to him when he just KNEW "that big 6.2 is gonna be super loud!".
• Under load (accelerating, etc.) the sound level inside and out definitely picks up. Still nothing close to loud. As a comparison, my wife's Bonneville GXP is louder and it's bone stock. There's just still so much "stuff" in this exhaust the noise never has a chance. At full tilt, it has a rather satisfying sound IMHO.
• Sounds much more like a hot sports car than a truck. Smooth and mellow. No cackling, popping, etc. Not sure if it's the pipe, resonator or what, but smooth and mellow is the only way I can describe it. Other than maybe a bit more throaty/meaty, it's essentially the stock sound but louder under throttle. Which, for me was perfect as I liked the way it sounded stock, just waaaay too quite.
• Mileage? Well, jury is out. Only have a few miles on it, so I'm not passing judgement yet. BUT, I took my usual path home on the commute, typical traffic, etc. I always always get right about 20, but yesterday I got a tick over 21. Might just be coincidence. On the ~20 mi drive from the shop I actually had 22 mpg. Which seems odd since I seriously flogged the piss out of it. Either way, doesn't seemed to have hurt it any.

Downsides? Well, if you want it loud, you're going to need to get more aggressive. I actually ran for a while with the entire catback removed, and even that wasn't overly loud outside the truck. Problem was the dump right under the cab.

 

I did notice a bit of what I think was flapper noise when revved at idle. To be fair, it could have just been the cold, new pipes ticking a bit, not sure. I'll do some more playing around with it, but I suspect that the less restricted path along with the flapper is making the flapper "flap around" more aggressively and literally slamming it full open/full closed with prejudice. This would explain what I was hearing. Kinda a tick/ping with an associated whooshing noise. But barely perceptible. I was really listening hard for anything I didn't approve of. And I only heard this at the tailpipe, can't hear elsewhere. I'll probably band clamp it open and see if it drones. If it doesn't and the tick goes away, I'll just pull the flapper.

 

I left the flapper in for a couple of reasons. 1 - It's never given me any issues, 2 - I was hoping it would quell any possible drone and 3 - who knows, maybe it does give V4 a bit more torque. Well it doesn't drone at all, but I don't know 100% for certain that I can attribute this to the flapper still in place.

 

Assuming all goes well the next week or so, the next step is a Y and duals out the back.

 

I tried explaining the same thing to people off and on for six months. Over the years I spent a bundle on exhaust, but for mild rumble till you hammer it. Muffler delete works good.

[bruklnboy]

got my Borla today, waiting til thurs to use my friends lift to install it

[mdmischief]

got my Borla today, waiting til thurs to use my friends lift to install it

Make sure you have all the pipes you need. Mine is sitting at the dealership because it's missing a pipe for my crew cab. Such BS.

[Strykers_Inc]

Just finished installing the GM-Performance Borla Split pipe system. Pretty easy to do but a pain in the ass without a lift. Thanks goes out to Fondupont for providing sound advice. Will post pics later once I get my shop cleaned up.

['00SonomaZQ8]

Just finished installing the GM-Performance Borla Split pipe system. Pretty easy to do but a pain in the ass without a lift. Thanks goes out to Fondupont for providing sound advice. Will post pics later once I get my shop cleaned up.

Can't wait to see ad hear it!

[chevhot]

got my Borla today, waiting til thurs to use my friends lift to install it

congrats cant wait to hear it

[bruklnboy]

Make sure you have all the pipes you need. Mine is sitting at the dealership because it's missing a pipe for my crew cab. Such BS.

i Checked all pipes there, mine came from Borla its different then the GMPP setup that the dealer sells

[chevhot]

got my Borla today, waiting til thurs to use my friends lift to install it

is it Thursday yet

[bruklnboy]

is it Thursday yet

lol, few more hours but you will probally hear my doing 100 up i495 later will definitly post pix and try to upload a video

[bruklnboy]

 

 

OMG!!!!!!!!!! took about 15mins. Well Im not a engineer or a car guru but I didnt think that i would gain torque or HP but it did. Idk if its because of the airflow or the exhaust or both

It is way more responsive and felt like it shifted a little easier,definitly notiecable tho. ZERO DRONE in v4 and there was no sound change switching. I thought it would be louder but it definitly has a deep growl and is pretty loud at startup in garage, in the cab with windows down my sons and i had a normal spoken a conversation. with foot off the pedal you could barely barely hear it. 4000+ rpm you can still hold convo. Video I have on youtube is a hot start, i was worried it wouldnt be loud enough or too loud, but it is perfect. havent noticed any change with active noise cancellation or if it even effects it in any way. its quiet til bout 2000rpms then the tones start coming alive. I would highly recommend, i had my doubts, but 100x better than i expected. . amazing smooth and subtle at low rpms. The neighbors may not like the start up from echo in garage, and is loud if you get on her, but normal driving is fine and dont think cops would give you a look, but watch out if you hit it lmao, heads will turn

 

[chevhot]

OMG!!!!!!!!!! took about 15mins. Well Im not a engineer or a car guru but I didnt think that i would gain torque or HP but it did. Idk if its because of the airflow or the exhaust or both

It is way more responsive and felt like it shifted a little easier,definitly notiecable tho. ZERO DRONE in v4 and there was no sound change switching. I thought it would be louder but it definitly has a deep growl, in the cab with windows down my sons and i had a normal spoken a conversation. with foot off the pedal you could barely barely hear it. 4000+ rpm you can still hold convo. Video I have on youtube is a hot start, i was worried it wouldnt be loud enough or too loud, but it is perfect. havent noticed any change with active noise cancellation or if it even effects it in any way. its quiet til bout 2000rpms then the tones start coming alive. I would highly recommend, i had my doubts, but 100x better than i expected. . amazing smooth and subtle at low rpms

www.youtube.com/watch?v=B3Z_sboWpL

OK now i am pissed i didn't just wait for mine it sounds fing great just wish they had one for my setup going to call them again to see when they will have one for mine if not i will just do what i was going to do and add i piece of pipe to make up the diff

[chevhot]

installed new bolra this morning sounds great

[desert]

Magnaflow 15318 - $863.26 - (custom tip added)

 

 

 

[chevhot]

video of my borla 6.2 ATAK

 

 

 

 

 

 

[Ljrussell94]

FYI:

 

 

Just got off the phone with Borla.

 

Asked a lot of questions and this is the info I got from them.......

 

 

The Borla 6.2L GM catback systems are as follows:

 

 

"ATAK" muffler series (the loudest ones):

 

Part #140572 & #140577

 

They have an MSRP of $1,174.00, but can be found cheaper online.

 

http://www.borla.com/products/silveradosierra_1500_catback_exhaust_atak_part__140572.html

 

http://www.borla.com/products/silveradosierra_1500_catback_exhaust_atak_part__140577.html

 

 

 

"S-Type" muffler series (medium loudness):

 

Part #140571 & #140576

 

http://www.borla.com/products/silveradosierra_1500_catback_exhaust_stype_part__140571.html

 

http://www.borla.com/products/silveradosierra_1500_catback_exhaust_stype_part__140576.html

 

 

 

"Touring" muffler series (least aggressive):

 

Part# 140570

 

http://www.borla.com/products/silveradosierra_1500_catback_exhaust_touring_part__140570.html

 

 

 

Unfortunately these are only available for the Crew Cab "Short Box" and not the Crew Cab "Standard box" like I have. I asked him whether they would be coming out with a CC Standard Box variant, but he said at this time it wasn't in the plans. This is probably due to the fact most people order the Short Box configuration with their Sierra Denali.

 

The system only comes in a straight back (out the bumper) or double tip behind the rear passenger tire configuration. There is no option for 45* or 90* dual rear exit. Unfortunate.

 

 

 

 

 

 

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They also offer another system that has to be ordered through GM directly (or your local dealership).

 

It is GM part# 19303341 (for CC Standard Box) and has an MSRP of $1,249

 

It is only offered in their "touring" muffler, the mildest one they have.

 

 

 

All this news was quite upsetting. I really wanted a rear 45* exit with the "ATAK" muffler.

 

It looks like I'll be going the custom route and ordering the muffler I want and a stainless pipe kit to be custom bent by a muffler shop that uses a mandrel bending system.

 

Hope this info helps those looking.

Do you happen to have just the part number for those mufflers? Preferbly the s type muffler for the 6.2. Thanks