Backfire when you decerate? No... - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

CamaroFred · 10-08-2016, 01:01 AM

So reading some threads here concerning exhausts I've come to the conclusion that there are many forum members who do not know what backfire is.

There is confusion describing the gurgling noise our exhausts make when using engine braking.

Those familiar with carburetors can quit reading now.
It seems members of our forum want to learn so here I go defining backfire and related noise.

BACKFIRE:
When internal combustion engines were created a method had to be devised to limit the fuel and air to the motor so it wouldn't just run full blast until it blew up.
So a plate that could be changed from fully closed to fully open was placed before the intake.
Fuel had to be mixed in the correct proportions to the air to ensure a combustible mixture. The already invented venturi filled this need because the more air that passed through the funnel shape the higher a vacuum it would create which could draw fuel in the same proportion through a hole in the side of the venturi from a standing source (fuel bowl). The fuel bowl was replenished using a fuel pump and regulated with a float to maintain an acceptable level.

There were a lot of things that could go wrong with this system, but for the most part and as development continued it became fairly reliable.

When there was an issue it either didn't pass enough fuel or it passed to much fuel. When it passed to much fuel the excess fuel would pool in the intake manifold and when the concentration became high enough it would explode in the intake manifold.
A small amount would just pop (under the hood) and go out.
But if you had a real problem it would blow fire out of the carburetor and if it was strong enough it could destroy the carburetor and send fuel out in every direction and burn your car to the ground.
There were often operator error because of pumping the throttle or closing the choke too far or when you got pissed because it was to hot or cold or in between to start.

Mechanical issues could also case this. Like a bad float or a bit of dirt in the needle.

AFTERFIRE:
When more fuel is introduced to a cylinder than it can burn.
The unburned fuel is pushed out of the cylinder with the exhaust gases and if the fuel builds up in the exhaust system it will burn. Usually these gas flames just pass through the exhaust but it can also lead to damage if confined.

GURGLE:
The noise you hear in a fuel injected 21st century vehicle when decelerating.
Those pops when decelerating are produced when no fuel is introduced to a cylinder. There is no combustion and the exhaust does not rush out of the cylinder. So there are pulses of air coming through the exhaust instead of a steady flow of exhaust gases.
The different lengths of the exhaust paths as well as the intermittent fuel shutoff per cylinder can make the sound seem random.

The solution if you don't like the sound is to avoid engine braking. Use the brakes instead of downshifting. Upshifting or sliding into neutral.

TLDR? Me either

I hope it helps.

JCunningham · 10-08-2016, 01:47 AM

gurgle gurgle. i like the gurgle.

Zezima · 10-08-2016, 01:54 AM

I have a full blown straight pipe from engine to tips, 4 cat deleted and all, plus a true dual. It's popping when i'm pulling out of the driveway.

Gunmetal Speedster · 10-08-2016, 01:59 AM

Quote:

Originally Posted by JCunningham

gurgle gurgle. i like the gurgle.

Gurgle is gooooood

redcoats1976 · 10-08-2016, 03:09 AM

i miss the backfire my old pontiac would make when you took your foot off the gas at 130...

Dmpsix · 10-08-2016, 07:53 AM

My LT headers all the way back down to muffler delete... my car backfires going around the drive through at Burger King!

I LOVE it... there was a thread here a while back where you could essentially have a custom dyno tune and have it tuned out

Not sure why anyone would actually want that tuned out!

Homeless Man · 10-08-2016, 08:08 AM

Yea not sure why many people don't like this. One of the best things about the exhaust. Have you guys heard the Huracan pop and crackle?? Pretty much every time you let off the gas it's amazing.

christianchevell · 10-08-2016, 09:00 AM

Deceleration "popping", "Gurgle" what ever you want to call it is from the fuel cutoff and the air giving air in the exhaust with the heat of the exhaust and the excess fuel causing it to ignite with those little damn near glowing o2 sensors helping and the element of the cat and any surface that can help to hold heat and ignite the fuel with air. Yes there are intake and exhaust back fires the latter being more pronounced and getting your attention.

With more radical cams I would have to change the elements of those foam LYNX Edelbrock filter elements over the years from small flameouts in Small block Chevy's but liked their look. And their reusable filter elements. Then "gurgle", not a good description unless your choking the decal popping to more mellow sound than having the exhaust more wide open where it does "pop". The sound is the fuel catching fire in pulses when there is enough air to ignite it in the exhaust suddenly causing the pops.

Its just awesome sounding to down shift with the exhaust open coming up to a stop or where needed and pronounce that yes your not just another Camaro on the road as the ricers dream of being able to make the sound and spend late nights with their Fart trumpets blowing furiously trying to be like us only to always come up short, or Farty sounding and just make them tin cans Scream "Douche Bag" coming down the road lookout its a Honda boy....LOL As yes they by far are a Plaque and Kids don't let your babies grow up to be Ricers.....

http://www.revheads.com.au/images/Pa...p/LYNX1000.jpg

Now some guys who are more of a tuner are not what you will see more on the road around here its more of guys slapping FI on the little engine and then doing suspension mods and driving around in parking lots by cones sure it looks fun even see Corvettes doing it, but you cannot listen to them for long before you notice how damn raspy they deliberately try to alter their exhaust to be and just how Ass Clown it is with the Butt Trumpets managing to make some little popping sound from a weak POS even if they have made it work right and its just damn hilarious to roll up to a stop downshifting next to them and make their EGO go in the toilet , then take off next to their enormous Fart trumpets and not only blow their doors off but also drown out their Obnoxious noise with V-8 Roar.
It makes me feel like Dr.Evil saying "Yes its a v-8 Baby" with my pinky in my mouth at the stop light....as yes I have been asked that and many other things just trying to wait for the Light.... SO yes that's my rant, " It's a V-8 Baby" WOMP, WOMP, WOMP, pop pop pop pop .

Hattori Hanzo · 10-08-2016, 11:18 AM

My exhaust definitely let's the world know I'm decelerating...but hey, who doesn't like Rice Krispies?

Dmpsix · 10-08-2016, 11:37 AM

Quote:

Originally Posted by Homeless Man

Yea not sure why many people don't like this. One of the best things about the exhaust. Have you guys heard the Huracan pop and crackle?? Pretty much every time you let off the gas it's amazing.

Dude all the time, I see at least 4 Hurucans a day!

URBAN LEGEND · 10-08-2016, 12:45 PM

The undisputed stock king of pop is the Jaguar F Type R.

Dmpsix · 10-08-2016, 02:07 PM

Quote:

Originally Posted by URBAN LEGEND

The undisputed stock king of pop is the Jaguar F Type R.

I thought it was Michael Jackson!

frankwjr · 10-08-2016, 02:26 PM

Quote:

Originally Posted by christianchevell

Deceleration "popping", "Gurgle" what ever you want to call it is from the fuel cutoff and the air giving air in the exhaust with the heat of the exhaust and the excess fuel causing it to ignite with those little damn near glowing o2 sensors helping and the element of the cat and any surface that can help to hold heat and ignite the fuel with air. Yes there are intake and exhaust back fires the latter being more pronounced and getting your attention.

With more radical cams I would have to change the elements of those foam LYNX Edelbrock filter elements over the years from small flameouts in Small block Chevy's but liked their look. And their reusable filter elements. Then "gurgle", not a good description unless your choking the decal popping to more mellow sound than having the exhaust more wide open where it does "pop". The sound is the fuel catching fire in pulses when there is enough air to ignite it in the exhaust suddenly causing the pops.

Its just awesome sounding to down shift with the exhaust open coming up to a stop or where needed and pronounce that yes your not just another Camaro on the road as the ricers dream of being able to make the sound and spend late nights with their Fart trumpets blowing furiously trying to be like us only to always come up short, or Farty sounding and just make them tin cans Scream "Douche Bag" coming down the road lookout its a Honda boy....LOL As yes they by far are a Plaque and Kids don't let your babies grow up to be Ricers.....

http://www.revheads.com.au/images/Pa...p/LYNX1000.jpg

Now some guys who are more of a tuner are not what you will see more on the road around here its more of guys slapping FI on the little engine and then doing suspension mods and driving around in parking lots by cones sure it looks fun even see Corvettes doing it, but you cannot listen to them for long before you notice how damn raspy they deliberately try to alter their exhaust to be and just how Ass Clown it is with the Butt Trumpets managing to make some little popping sound from a weak POS even if they have made it work right and its just damn hilarious to roll up to a stop downshifting next to them and make their EGO go in the toilet , then take off next to their enormous Fart trumpets and not only blow their doors off but also drown out their Obnoxious noise with V-8 Roar.
It makes me feel like Dr.Evil saying "Yes its a v-8 Baby" with my pinky in my mouth at the stop light....as yes I have been asked that and many other things just trying to wait for the Light.... SO yes that's my rant, " It's a V-8 Baby" WOMP, WOMP, WOMP, pop pop pop pop .

OMFG!!!! ROFL....readin my mind bro???

NC_SS · 10-08-2016, 03:16 PM

Quote:

Originally Posted by Homeless Man

Yea not sure why many people don't like this. One of the best things about the exhaust. Have you guys heard the Huracan pop and crackle?? Pretty much every time you let off the gas it's amazing.

This is what sparked my love for the crackle and pop on exhausts

Heard a Aventador go WOT by me and when it started to decel that sound was godly

10-08-2016, 01:01 AM	#1
CamaroFred Drives: Miss Con Ception Join Date: Aug 2016 Location: Chicagoland Posts: 2,998	Backfire when you decerate? No... So reading some threads here concerning exhausts I've come to the conclusion that there are many forum members who do not know what backfire is. There is confusion describing the gurgling noise our exhausts make when using engine braking. Those familiar with carburetors can quit reading now. It seems members of our forum want to learn so here I go defining backfire and related noise. BACKFIRE: When internal combustion engines were created a method had to be devised to limit the fuel and air to the motor so it wouldn't just run full blast until it blew up. So a plate that could be changed from fully closed to fully open was placed before the intake. Fuel had to be mixed in the correct proportions to the air to ensure a combustible mixture. The already invented venturi filled this need because the more air that passed through the funnel shape the higher a vacuum it would create which could draw fuel in the same proportion through a hole in the side of the venturi from a standing source (fuel bowl). The fuel bowl was replenished using a fuel pump and regulated with a float to maintain an acceptable level. There were a lot of things that could go wrong with this system, but for the most part and as development continued it became fairly reliable. When there was an issue it either didn't pass enough fuel or it passed to much fuel. When it passed to much fuel the excess fuel would pool in the intake manifold and when the concentration became high enough it would explode in the intake manifold. A small amount would just pop (under the hood) and go out. But if you had a real problem it would blow fire out of the carburetor and if it was strong enough it could destroy the carburetor and send fuel out in every direction and burn your car to the ground. There were often operator error because of pumping the throttle or closing the choke too far or when you got pissed because it was to hot or cold or in between to start. Mechanical issues could also case this. Like a bad float or a bit of dirt in the needle. AFTERFIRE: When more fuel is introduced to a cylinder than it can burn. The unburned fuel is pushed out of the cylinder with the exhaust gases and if the fuel builds up in the exhaust system it will burn. Usually these gas flames just pass through the exhaust but it can also lead to damage if confined. GURGLE: The noise you hear in a fuel injected 21st century vehicle when decelerating. Those pops when decelerating are produced when no fuel is introduced to a cylinder. There is no combustion and the exhaust does not rush out of the cylinder. So there are pulses of air coming through the exhaust instead of a steady flow of exhaust gases. The different lengths of the exhaust paths as well as the intermittent fuel shutoff per cylinder can make the sound seem random. The solution if you don't like the sound is to avoid engine braking. Use the brakes instead of downshifting. Upshifting or sliding into neutral. TLDR? Me either I hope it helps.

10-08-2016, 01:47 AM	#2
JCunningham Drives: 2017 2SS M6 Join Date: Jun 2013 Location: WNY Posts: 7,070	gurgle gurgle. i like the gurgle. __________________ real ZL1 wheels and brakes, 285/305 Michelin Pilot Super Sports, Pray ported Intake manifold, Soler Throttle Body, Rotofab intake, EFI Tuning Flex fuel kit, full American Racing Headers Exhaust, 1 7/8" w/ cats H pipe and mufflers. Full 1LE suspension, with BMR adjustable sway bars and links, GM aluminum cradle bushings, Hurst shifter with lighter reverse spring, TWM shifter knob, Tick level 1 transmission. I should have bought a ZL1

10-08-2016, 08:08 AM	#7
Homeless Man Homeless Life Chose Me Drives: LS3 (sold 4/21) Join Date: Nov 2014 Location: Streets of Philly Posts: 3,650	Yea not sure why many people don't like this. One of the best things about the exhaust. Have you guys heard the Huracan pop and crackle?? Pretty much every time you let off the gas it's amazing. __________________ Pity a man in familiar places, who yet feels like a stranger.

10-08-2016, 09:00 AM	#8
christianchevell old school chevy rodder Drives: 2013 2SS/RS Manual,DM exhaust,CRT Join Date: Jul 2012 Location: Oregon Posts: 5,587 View My Garage	Deceleration "popping", "Gurgle" what ever you want to call it is from the fuel cutoff and the air giving air in the exhaust with the heat of the exhaust and the excess fuel causing it to ignite with those little damn near glowing o2 sensors helping and the element of the cat and any surface that can help to hold heat and ignite the fuel with air. Yes there are intake and exhaust back fires the latter being more pronounced and getting your attention. With more radical cams I would have to change the elements of those foam LYNX Edelbrock filter elements over the years from small flameouts in Small block Chevy's but liked their look. And their reusable filter elements. Then "gurgle", not a good description unless your choking the decal popping to more mellow sound than having the exhaust more wide open where it does "pop". The sound is the fuel catching fire in pulses when there is enough air to ignite it in the exhaust suddenly causing the pops. Its just awesome sounding to down shift with the exhaust open coming up to a stop or where needed and pronounce that yes your not just another Camaro on the road as the ricers dream of being able to make the sound and spend late nights with their Fart trumpets blowing furiously trying to be like us only to always come up short, or Farty sounding and just make them tin cans Scream "Douche Bag" coming down the road lookout its a Honda boy....LOL As yes they by far are a Plaque and Kids don't let your babies grow up to be Ricers..... http://www.revheads.com.au/images/Pa...p/LYNX1000.jpg Now some guys who are more of a tuner are not what you will see more on the road around here its more of guys slapping FI on the little engine and then doing suspension mods and driving around in parking lots by cones sure it looks fun even see Corvettes doing it, but you cannot listen to them for long before you notice how damn raspy they deliberately try to alter their exhaust to be and just how Ass Clown it is with the Butt Trumpets managing to make some little popping sound from a weak POS even if they have made it work right and its just damn hilarious to roll up to a stop downshifting next to them and make their EGO go in the toilet , then take off next to their enormous Fart trumpets and not only blow their doors off but also drown out their Obnoxious noise with V-8 Roar. It makes me feel like Dr.Evil saying "Yes its a v-8 Baby" with my pinky in my mouth at the stop light....as yes I have been asked that and many other things just trying to wait for the Light.... SO yes that's my rant, " It's a V-8 Baby" WOMP, WOMP, WOMP, pop pop pop pop . __________________ 2021 Wild Cherry ZL1 A10, Sunroof, Data, Carbon, Nav, RotoFab Dry CAI, Elite x2, Borla ATK, Driveshaft shop

10-08-2016, 11:18 AM	#9
Hattori Hanzo Drives: 2011 Camaro 2SS Join Date: Aug 2016 Location: Peoria, AZ Posts: 69 View My Garage	My exhaust definitely let's the world know I'm decelerating...but hey, who doesn't like Rice Krispies? __________________ I must be honest here....I love driving it. It is so choice. If you have the means, I highly recommend picking one up. - Ferris Bueller

10-08-2016, 01:54 AM	#3
Zezima Drives: 2014 Camaro 2LT/RS Join Date: Apr 2015 Location: Texas Posts: 347 View My Garage	I have a full blown straight pipe from engine to tips, 4 cat deleted and all, plus a true dual. It's popping when i'm pulling out of the driveway.

10-08-2016, 03:09 AM	#5
redcoats1976 Drives: LT W/2LT,blue metallic Join Date: Jul 2016 Location: central florida Posts: 4,915	i miss the backfire my old pontiac would make when you took your foot off the gas at 130...

10-08-2016, 07:53 AM	#6
Dmpsix Drives: Black L99 2SS/RS Join Date: Mar 2014 Location: San Antonio, TX Posts: 1,862	My LT headers all the way back down to muffler delete... my car backfires going around the drive through at Burger King! I LOVE it... there was a thread here a while back where you could essentially have a custom dyno tune and have it tuned out Not sure why anyone would actually want that tuned out!

10-08-2016, 12:45 PM	#11
URBAN LEGEND Drives: 20 X3M CP & 19 ZL1 1LE A10 Join Date: Jun 2013 Location: Brenham, TX Posts: 3,517	The undisputed stock king of pop is the Jaguar F Type R. __________________ 🔺22 RS E TRON GT 🔺21 Model S Plaid