L99 Exhaust AFM/Drone worries - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Pongo · 06-21-2020, 12:08 PM

Hey guys, happy Father’s Day. I’ve searched the forums and was trying to find something more concrete on some of my worries. I definitely want to get some extra flow and growl out of the exhaust, but I’m worried with it being a daily that some of the catbacks might drone my brain into liquid on the highway going to work. I’ve looked at Borla, Solo with J pipes, and some QTP cutouts and was wondering what the guys on here thought. I never see videos in cabin. Only start up vids so it’s hard to tell what’s best all around. The Solo catback seems appealing as they claim even the afm doesn’t sound bad with the kit

StingrayblueSS · 06-21-2020, 01:16 PM

Most people tune it out or buy a range device if the don't want to tune their car.

Avenging Orange · 06-21-2020, 01:22 PM

I would suggest some more reading. There are tons of answers. Of course, headers are your best option. Added to the stock system = no drone.
If headers are not an option...deleting the bulky L99 resonators and replacing it with a resonated x pipe. The L99 resonator is the biggest sound killer.
These are the most cost effective options. Cat back systems, j pipes etc,. are just more costly than they are worth.

InFiD3ViL · 06-21-2020, 01:29 PM

There are some exhausts that are designed specifically for the L99 to combat the AFM transitions/drone. If you are intent on keep AFM then I would look for something designed with it in mind. They will usually mention AFM/DOD or Automatic in the description and will normally contain some sort of forward resonator for this reason.

Also consider your future goals with the car regarding mods, including disabling AFM via tune. If you plan to go with long tube headers or pretty much any other exhaust mods in the future, disabling AFM would be a good idea. It will give you more options for exhaust without having to worry about the AFM drone.

Keep in mind there are 2 types of drone you may have read us talk about here. The AFM drone and general exhaust drone. They are 2 entirely separate things.

Pongo · 06-21-2020, 03:01 PM

Well I’m not looking for anything show stopping, I just want some aggression and power in the note. I don’t think I’ll be adding too much on the side of performance. I would rather wait a few years so I can get a daily and a weekend warrior

pyroguy · 06-21-2020, 03:30 PM

First off, welcome to the forums!

Exhaust video

Here's a clip of my exhaust with kooks headers with high flow cats and Solo Mach xl catback. I have AFM/DOD still enabled when I took this video. I only deleted it when I did my cam swap and never had any issues. Solo exhaust is awesome!

lemontwist · 06-21-2020, 04:15 PM

i took my good sounding drone free magnaflow off my ls3 and put it on the l99

it no longer sounds good to me. it has a forward resonator the l99 needs more than a cat back exhaust to sound good. the tune will fix the dod fart sound. i'll will do the ls3 conversion at some point.
https://www.autohance.com/magnaflow-...yABEgLF8fD_BwE

pyroguy · 06-21-2020, 04:45 PM

I will disagree that a L99 NEEDS more than a catback to sound good. Before I installed my headers I had my Solo Mach XL catback by itself and it sounded great. Mild while cruising inside the car and then loud at WOT. Adding headers with high flow cats was just icing on the cake. Even with AFM/DOD enabled I would get compliments from friends after we got done cruising. The reason I went with Solo vs something else was because it had a muscle car sound without having the drone. The previous owner of my car put in some awful cheap mufflers that droned ferociously and I didn’t want to risk replacing drone with drone. Sadly, I don’t have any video clips of pre headers, but the only difference pre vs post headers was volume (and of course power gain with headers).

lemontwist · 06-21-2020, 05:58 PM

Quote:

Originally Posted by pyroguy

I will disagree that a L99 NEEDS more than a catback to sound good. Before I installed my headers I had my Solo Mach XL catback by itself and it sounded great. Mild while cruising inside the car and then loud at WOT. Adding headers with high flow cats was just icing on the cake. Even with AFM/DOD enabled I would get compliments from friends after we got done cruising. The reason I went with Solo vs something else was because it had a muscle car sound without having the drone. The previous owner of my car put in some awful cheap mufflers that droned ferociously and I didn’t want to risk replacing drone with drone. Sadly, I don’t have any video clips of pre headers, but the only difference pre vs post headers was volume (and of course power gain with headers).

you had this? because i was thinking the resonator with a muffler delete could sound good that looks like what that is with j pipes.
https://shop-solo-performance.com/en...automatic.html
the video with the sound clip might be more than i was hoping for LOL
sounds nasty in a good way

ss camaro-monte · 06-21-2020, 06:04 PM

As someone who went through the same dilemma as you I would ultimately get a range device or tune. Here is how mine went. The factory drone bothered me in stock form. It was so annoying!
2015 L99
First I went with a solo xl cataback with j pipe system and removed the resonator. Sounded great but there was even more drone if I didn't shift the paddles myself but when I shifted myself it sounded great. How it should have from the factory.

Well then I wanted more performance so I got a vararam, full length headers and a tune. Dear God is all I can say. AFM was tuned out and the car picked up almost 50rwhp. Drives like a totally different car! It is much louder now but really only when starting it or getting on it. Otherwise it isn't that loud but when I get one it you can hear it more than half a mile down the road easily.

If your car isn't under warranty tune it! Mine still had 8 months left and I couldn't stand the AFM. I couldn't wait and tuned it. Totally different animal now.

pyroguy · 06-21-2020, 08:27 PM

Quote:

Originally Posted by lemontwist

you had this? because i was thinking the resonator with a muffler delete could sound good that looks like what that is with j pipes.
https://shop-solo-performance.com/en...automatic.html
the video with the sound clip might be more than i was hoping for LOL
sounds nasty in a good way

I had the Mach xl catback coupe version. I have always been able to drive around with the radio at volume 6 and still hold a conversation in the car. Even cammed now is a little loud on a cold start, but a warm idle is still a little tame. I can even still leave the radio volume at 6 cruising on the highway. It doesn't get crazy until I really get into the throttle.

Quote:

Originally Posted by ss camaro-monte

As someone who went through the same dilemma as you I would ultimately get a range device or tune. Here is how mine went. The factory drone bothered me in stock form. It was so annoying!
2015 L99
First I went with a solo xl cataback with j pipe system and removed the resonator. Sounded great but there was even more drone if I didn't shift the paddles myself but when I shifted myself it sounded great. How it should have from the factory.

Well then I wanted more performance so I got a vararam, full length headers and a tune. Dear God is all I can say. AFM was tuned out and the car picked up almost 50rwhp. Drives like a totally different car! It is much louder now but really only when starting it or getting on it. Otherwise it isn't that loud but when I get one it you can hear it more than half a mile down the road easily.

If your car isn't under warranty tune it! Mine still had 8 months left and I couldn't stand the AFM. I couldn't wait and tuned it. Totally different animal now.

Drone with a Solo exhaust? Did you adjust the J pipes? Even now with my cam I had a little drone so I lengthened my j pipes and it went away.

ss camaro-monte · 06-21-2020, 09:40 PM

We could never fully get the drone out. We adjusted the j pipes and it helped some but the bottom line is it makes the drone in stock form more pronounced. That could be because we removed the resonator as well.

I also forgot after the catback I went to the solo high flow cats that was the biggest difference imo. Drone was only there when I didn't shift and let the transmission shift itself. Bottom line is AFM sucks for these cars. 6th gen they got it way better and it is a more seamless function. I lost maybe .5 miles per gallon with it tuned out but there is no reason not to do a tune if you are out of warranty. Made the whole experience of driving the car 5x better.

Imo tune out AFM first and tune the car. Everyone always said just tune it and I was worried about warranty and everything but it was a pointless worry now that I look back. Put it this way, if I had to do an axle back and tune or full exhaust and no tune I would take the tune every time. I believe it is the tune that not only solves the drone problem completely but it also just makes this car drive like a sports car. Car finally feels fast.

06-21-2020, 12:08 PM	#1
Pongo Drives: 2015 Camaro 1SS RS L99 Join Date: Jun 2020 Location: Tulsa, Oklahoma Posts: 3	L99 Exhaust AFM/Drone worries Hey guys, happy Father’s Day. I’ve searched the forums and was trying to find something more concrete on some of my worries. I definitely want to get some extra flow and growl out of the exhaust, but I’m worried with it being a daily that some of the catbacks might drone my brain into liquid on the highway going to work. I’ve looked at Borla, Solo with J pipes, and some QTP cutouts and was wondering what the guys on here thought. I never see videos in cabin. Only start up vids so it’s hard to tell what’s best all around. The Solo catback seems appealing as they claim even the afm doesn’t sound bad with the kit

06-21-2020, 01:16 PM	#2
StingrayblueSS Drives: 2013 Camaro SS Join Date: Feb 2017 Location: Indiana Posts: 901	Most people tune it out or buy a range device if the don't want to tune their car. __________________ 2013 Camaro SS Kooks Headers Vararam DRX 1le Differential 3.91 Bo White throttle body Magnaflow Competition Exhaust 12.391 112 MPH 10/05/19

06-21-2020, 01:22 PM	#3
Avenging Orange Drives: 2010 Inferno Orange 2SS/RS Join Date: Apr 2010 Location: Clermont, IN Posts: 3,297	I would suggest some more reading. There are tons of answers. Of course, headers are your best option. Added to the stock system = no drone. If headers are not an option...deleting the bulky L99 resonators and replacing it with a resonated x pipe. The L99 resonator is the biggest sound killer. These are the most cost effective options. Cat back systems, j pipes etc,. are just more costly than they are worth. __________________ 2010 Inferno Orange 2SS/RS M6 Black Leather, Sun Roof, OBX Headers, Borla touring axle back, Cold Air Inductions CAI , non synthetic fluids, BMR total bushing upgrade/1" lowering springs, DSE 32mm rear sway bar. GM fe4 shocks/struts/LCA's, AAM 3.91 diff, Vertini RFS1.8 20x9 +30. Conti ExtremeContact Sport 275/35/20. sjm autoprod ABL dash kit. Mike Norris tuned 413/419. Avenging Orange: 43 years of not buying into the Hype........and damn proud of it!! https://youtu.be/9JD9it6SmB8 https://youtu.be/xmelTlEzI34 KICKING CANCERS ASS SINCE 2015!!

06-21-2020, 01:29 PM	#4
InFiD3ViL Drives: 2010 CGM 2SS/RS LS3 Swapped A6 Join Date: Sep 2016 Location: Spring Hill, FL Posts: 4,575	There are some exhausts that are designed specifically for the L99 to combat the AFM transitions/drone. If you are intent on keep AFM then I would look for something designed with it in mind. They will usually mention AFM/DOD or Automatic in the description and will normally contain some sort of forward resonator for this reason. Also consider your future goals with the car regarding mods, including disabling AFM via tune. If you plan to go with long tube headers or pretty much any other exhaust mods in the future, disabling AFM would be a good idea. It will give you more options for exhaust without having to worry about the AFM drone. Keep in mind there are 2 types of drone you may have read us talk about here. The AFM drone and general exhaust drone. They are 2 entirely separate things. __________________ 2010 CGM Camaro 2SS LS3 Swapped A6 - GPI LS3 SS1 .647/.638, (224/237, 112 +4, 7º overlap) on CamMotion 8620 core, BTR Platinum .660" Dual Spring kit w/titanium retainers, CHE bronze trunnion upgrade, stock heads milled @ .015, Melling HV 10296 oil pump, TSP 1-7/8" long tube headers (W/Catless Off-road Pipes), Corsa Xtreme 3" Catback, GPI Ported/Rod Mod Intake, Stage 2 Ported Throttle Body, Vararam OTR CAI, Mike Norris Gen 2 catch can + GM 1LE clean side separator, 160º thermostat - Megan Racing adjustable coilovers (lowered 1.75"), MRR M017 10/11" wheels-Tuned by Ryan @ GPI

06-21-2020, 03:30 PM	#6
pyroguy Started#gottalovethatblue Drives: ABM #831 Join Date: Apr 2013 Location: TN Posts: 6,919 View My Garage	First off, welcome to the forums! Exhaust video Here's a clip of my exhaust with kooks headers with high flow cats and Solo Mach xl catback. I have AFM/DOD still enabled when I took this video. I only deleted it when I did my cam swap and never had any issues. Solo exhaust is awesome! __________________ '10 Camaro 2SS/RS \| Aqua Blue #831 of 3,903 \| Silver Stripes Check out my build thread

06-21-2020, 03:01 PM	#5
Pongo Drives: 2015 Camaro 1SS RS L99 Join Date: Jun 2020 Location: Tulsa, Oklahoma Posts: 3	Well I’m not looking for anything show stopping, I just want some aggression and power in the note. I don’t think I’ll be adding too much on the side of performance. I would rather wait a few years so I can get a daily and a weekend warrior

06-21-2020, 04:15 PM	#7
lemontwist Drives: 12 2SS/RS L99,11 2SS/RS LS3totaled Join Date: Jun 2019 Location: mooresville nc Posts: 1,048	i took my good sounding drone free magnaflow off my ls3 and put it on the l99 it no longer sounds good to me. it has a forward resonator the l99 needs more than a cat back exhaust to sound good. the tune will fix the dod fart sound. i'll will do the ls3 conversion at some point. https://www.autohance.com/magnaflow-...yABEgLF8fD_BwE Attached Images

06-21-2020, 04:45 PM	#8
pyroguy Started#gottalovethatblue Drives: ABM #831 Join Date: Apr 2013 Location: TN Posts: 6,919 View My Garage	I will disagree that a L99 NEEDS more than a catback to sound good. Before I installed my headers I had my Solo Mach XL catback by itself and it sounded great. Mild while cruising inside the car and then loud at WOT. Adding headers with high flow cats was just icing on the cake. Even with AFM/DOD enabled I would get compliments from friends after we got done cruising. The reason I went with Solo vs something else was because it had a muscle car sound without having the drone. The previous owner of my car put in some awful cheap mufflers that droned ferociously and I didn’t want to risk replacing drone with drone. Sadly, I don’t have any video clips of pre headers, but the only difference pre vs post headers was volume (and of course power gain with headers). __________________ '10 Camaro 2SS/RS \| Aqua Blue #831 of 3,903 \| Silver Stripes Check out my build thread

06-21-2020, 06:04 PM	#10
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 242	As someone who went through the same dilemma as you I would ultimately get a range device or tune. Here is how mine went. The factory drone bothered me in stock form. It was so annoying! 2015 L99 First I went with a solo xl cataback with j pipe system and removed the resonator. Sounded great but there was even more drone if I didn't shift the paddles myself but when I shifted myself it sounded great. How it should have from the factory. Well then I wanted more performance so I got a vararam, full length headers and a tune. Dear God is all I can say. AFM was tuned out and the car picked up almost 50rwhp. Drives like a totally different car! It is much louder now but really only when starting it or getting on it. Otherwise it isn't that loud but when I get one it you can hear it more than half a mile down the road easily. If your car isn't under warranty tune it! Mine still had 8 months left and I couldn't stand the AFM. I couldn't wait and tuned it. Totally different animal now.

06-21-2020, 09:40 PM	#12
ss camaro-monte Drives: 2015 camaro 2ss, 87 monte ss Join Date: Jun 2016 Location: Houston Posts: 242	We could never fully get the drone out. We adjusted the j pipes and it helped some but the bottom line is it makes the drone in stock form more pronounced. That could be because we removed the resonator as well. I also forgot after the catback I went to the solo high flow cats that was the biggest difference imo. Drone was only there when I didn't shift and let the transmission shift itself. Bottom line is AFM sucks for these cars. 6th gen they got it way better and it is a more seamless function. I lost maybe .5 miles per gallon with it tuned out but there is no reason not to do a tune if you are out of warranty. Made the whole experience of driving the car 5x better. Imo tune out AFM first and tune the car. Everyone always said just tune it and I was worried about warranty and everything but it was a pointless worry now that I look back. Put it this way, if I had to do an axle back and tune or full exhaust and no tune I would take the tune every time. I believe it is the tune that not only solves the drone problem completely but it also just makes this car drive like a sports car. Car finally feels fast.