BBK longtubes , off road H and bassani catback. It pops if you decel hard , but other than that is just pretty loud but I would say smooth sounding. It's all in the tune though ... The less pop the better , means it's not running rich
Do long tubes eliminate the infamous popping/gargle???
- Thread starter jaehow23
- Start date
OP,
There are a few variables in play when it comes to the "popping" you are interested in.
The sound you enjoy is due to fuel remaining "on" during an engine braking condition.
Following a long tip-out, you will notice your exhaust note significantly changes.
The change into the more "constant" tone/sound is when fuel is shut off.
Engine temperature, exhaust gas temperature, exhaust back pressure, fuel and spark are involved.
Fuel, back pressure and spark timing are what many would consider to be the major contributors.
In reality, for street vehicles, overrun fuel and back pressure can accomplish some dramatic decel conditions.
Personally, I like raspy exhaust systems, but do not enjoy overly-dramatic overruns.
I have a standard chambered muffler and no cats.
At high engine speeds, the overrun was so loud, it sounded like my mufflers were coming apart.
By removing some of the overrun fueling, the decels are now down to a more enjoyable level.
As a warning to the guys with cats (or emissions conscious), you have to be careful with excessively rich or long overruns.
Metallic and ceramic substrates can be over-temped during the long spirited runs.
If you are damaging the substrate, you are damaging the washcoat.
Poor washcoat = poor emissions.
Have fun!
There are a few variables in play when it comes to the "popping" you are interested in.
The sound you enjoy is due to fuel remaining "on" during an engine braking condition.
Following a long tip-out, you will notice your exhaust note significantly changes.
The change into the more "constant" tone/sound is when fuel is shut off.
Engine temperature, exhaust gas temperature, exhaust back pressure, fuel and spark are involved.
Fuel, back pressure and spark timing are what many would consider to be the major contributors.
In reality, for street vehicles, overrun fuel and back pressure can accomplish some dramatic decel conditions.
Personally, I like raspy exhaust systems, but do not enjoy overly-dramatic overruns.
I have a standard chambered muffler and no cats.
At high engine speeds, the overrun was so loud, it sounded like my mufflers were coming apart.
By removing some of the overrun fueling, the decels are now down to a more enjoyable level.
As a warning to the guys with cats (or emissions conscious), you have to be careful with excessively rich or long overruns.
Metallic and ceramic substrates can be over-temped during the long spirited runs.
If you are damaging the substrate, you are damaging the washcoat.
Poor washcoat = poor emissions.
Have fun!
hello, do you think you can elaborate on what you mean by the fuel being "on" or "shut off"?
also can you please clarify what you mean by "overrun"?
thanks
I don't really know what he means by overrun...
But the ECU has a feature - Decel Fuel Shut-Off (DFSO). When throttle is closed and some other parameters are met, a timer is started. When the timer elapses fuel is entirely shut off. Otherwise, during decel the ECU still tries to dose the correct amount of fuel.
I've noticed at modest (20-25 degrees) timing at very high manifold vacuums and just lean of stoich (15.0-17.0) I'll get pretty significant popping on decel. If the mixture goes further lean the popping stops, if the mixture is held richer (13.0 or lower), the popping stops. Timing has not seemed to have a major impact.
To stop the popping in the tune, add dashpot (closed throttle airflow), richen mixture, reduce timing to reduce generated torque so the engine actually decelerates. To make it pop, take out all the dashpot, bring it to stoich or slightly lean.
I love it personally. The Cobra does it if you have a hard deceleration, especially with a downshift. The Viper pops and crackles like crazy, especially if you just brake rather than downshift... I scared a dog the other day, it sounded like a couple of gun shots 
Long tubes should retain the pop. Honestly the only thing I can see eliminating is E-85, as previously stated because the gas may be less likely to burn up in the exhaust.
Long tubes should retain the pop. Honestly the only thing I can see eliminating is E-85, as previously stated because the gas may be less likely to burn up in the exhaust.
A couple guys said it - It's in the tune. I have my tune configured with aggressive deceleration fuel cut settings. This means when I let of the gas, the ECU is quickly shutting of my injectors and no additional fuel is making it into the cylinders/exhaust.
Indeed. My old tuner had mine popping like crazy. Sounded like a old beat up farm truck. Who in there right mind actually thinks that sounds good, is beyond me.
Now mine for the most part is nice and quiet. I prefer louder exhaust when I hit the gas pedal, not when I let off of it.
mine pops occasionally, like maybe one loud pop a week, otherwise its little crackles. Like making popcorn.
A little bit I think is fine. Mine was so bad that people would actually give me the wtf look. I hated it.
woah yeah that's no good. Mine's only a little bit, like in my video above. Any more and itd get annoying.
Although Tanya loves it :lol:
Haha. I think it is relative. A lot to someone is a little someone else. I'm not sure where I fall on the scale, if it did it too much I'd get annoyed but my wife and I both love it the way it is.
True. It's a personal preference. But after the initial retune after the header install, that popping was the loudest it's ever been. It's definitely tune related. After Kevin retuned my car is was almost gone. And I didn't even have to mention it to him.
I don't know if I believe it, but my wife says my car sounds totally different since I switched to e85. She said it's very deep sounding and has a distinctive sound, unlike any other mustang's in town. She hears it more than me when leaving and coming home.
E85 cars will sound different. We put cams in a customers 03 cobra, and on E it barely hits, on pump gas it hits a MEAN lick.
I somewhat regret installing my Kooks 1 5/8"s w/ the Off-road X since the pop is gone... Plus with the Stingers its just raw noise...
However, I only had Lund adjust the tune w/o an on dyno or datalogged revision. So who knows.
The best sound my car had was with the manifolds, Bassani Off-road X and Stingers.
However, I only had Lund adjust the tune w/o an on dyno or datalogged revision. So who knows.
The best sound my car had was with the manifolds, Bassani Off-road X and Stingers.
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My old 03 terminator vert (w/Borla Stingers + Bassani catted x) years ago popped and rumbled a lot on decel and I loved it. Sounded like a thunderstorm at times. My previous 2010 GT500 w/Borla catback, AR o/r x + AR longtubes done it as well, AFTER Kurgan tuned it. So the tune does play a role.
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