Exhaust banging on modified cars - whats the point?

Ev0

Ev0

Soldato
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My folks old 996 C4S sounded like a bag of spanner’s on startup/idle, sounded better when moving.

The Merc 6.3 is still one of the best sounding imho.
 
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It's fake because it's deliberately mapped in. Just like pops and bangs the OP is moaning about.

The ECU deliberately sends extra unburnt fuel into the exhaust to get the effect. It is entirely cosmetic on road cars.

Utter drivel. A V8 does not have "burble, pop or bang" mapped in...
 
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Utter drivel. A V8 does not have "burble, pop or bang" mapped in...

A recent C63 most definitely does.

Also more cyclinders != pops and bangs.

Cars have tuned exhaust sounds for no reason other than to make sounds which appeal to buyers. I don't get why that is so hard to believe. Every aspect is most likely deliberate.

Opening 10 seconds makes my point.

 
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Caporegime
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My Primera made many popping and crackling noises when the O2 sensor bung fell out (I hadn't tightened it up.)


So if you want them, just drill a big hole in your downpipe. The new craze! You wont believe this trick, doctors hate it! :p
 
Caporegime
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A burble on overrun happens because extra fuel is injected into cylinder. Guess who decides if that happens or not. There is practically no reason to do this other than for the side effects.


So explain my 1960's Renault 8 Gordini running on carburettors having it "mapped " in ??
 
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There's an MX-5 I (used to) see on my commute now and then, he purposefully made his heap of a car pop and bang all the damn time, really obnoxious. On the A1 when creeping to a roundabout he would leave a gap and speed up and roll-off to just make a load of noise. Quite a nob.

However, last week I was caught in a bit of a jam at one of these said roundabouts, I managed to creep through on my bike and what I saw at the front brought on a tear of joy. Turns out he'd rear-ended someone, badly. Front of barry-mobil was really crumpled in and there were bits of car all over the road.

Whilst I feel incredibly sorry for the other person, I could help but chuckle at the time.
 
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Soldato
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Because its still drawing fuel in when off throttle because carbs are horrendously inefficient. Think of it as mechanical mapping :D
Quite. But @Entai's point was (as I understand it) that the car hasn't been 'mapped' or set up to do it specifically, it's just how the systems work....as is the case with most older (10+ years) cars whether they are fuel injection or carbed.
 
Man of Honour
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Modern cars and modifiers make me laugh. But manufacturers aren't a lot better.

Tuned exhausts to open a flap above a certain RPM just for the noise.

Fake pops and bangs.

Real engine noise deliberately piped into the cabin.

Fake engine noise played into the cabin.
 
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Quite. But @Entai's point was (as I understand it) that the car hasn't been 'mapped' or set up to do it specifically, it's just how the systems work....as is the case with most older (10+ years) cars whether they are fuel injection or carbed.

Apart from very early EFI systems like Rover V8 "flapper" EFI for example, which was not clever enough to know the difference between idling and being at zero throttle input while in gear and moving, there is no technical reason for the car to do it contiously when off throttle without specific mapping to make that happen. Vast majority of EFI systems from the past 30 years or so (and certainly last 20) are fully capable of taking throttle position, speed, and RPM inputs to detect when the car is moving in gear with no throttle input, and shut off injectors entirely to save fuel and lower emissions. You don't hear a 90's Mondeo banging away in stock configuration!
 
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So explain my 1960's Renault 8 Gordini running on carburettors having it "mapped " in ??

And this post is appropriate for the context of the thread how?

I'm sure there was a time where timing and response times weren't good enough to avoid it, but that's not any car built in the last 20 years.
 
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Soldato
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My Capri V6 used to sort of pop on the over run, it was more of a dull, muted crackle actually but that was just how it was, it wasn't mapped in (no ECU of course, just dumb mechanical injection) although it did have a non-standard set of tubular manifolds & a pair of aftermarket exhausts. My ST220 also sometimes gives a single pop, very occasionally two on downshifts but it's by no means loud or continuous.

Some cars just sound broken. There is a lad who comes down my road every afternoon in a chrome wrapped Fiesta 1.0 Ecoboost & it sounds ridiculous. He "accelerates" for 4 seconds & then lets it pop & bang for 4 seconds and just repeats over & over, it's just so loud & intrusive for a car that barely increases in speed for all the noise it makes, it sounds knackered. On the flip side a guy in a C63 about 8 houses up, I could listen to that thing all day.
 
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Modern cars and modifiers make me laugh. But manufacturers aren't a lot better.

Tuned exhausts to open a flap above a certain RPM just for the noise.

Fake pops and bangs.

Real engine noise deliberately piped into the cabin.

Fake engine noise played into the cabin.

Whats the issue with the first one on the list?

I can see why you might want a quieter exhaust while trundling about (mindful of neighbours etc) and then open up the pipes when you want to press on.
 
Man of Honour
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Whats the issue with the first one on the list?

I can see why you might want a quieter exhaust while trundling about (mindful of neighbours etc) and then open up the pipes when you want to press on.
What's the reason for wanting a louder exhaust at all?
 
Caporegime
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What's the reason for wanting a louder exhaust at all?
It's quite common for the aural involvement of a vehicle to have a sizable impact of the overall enjoyment. In many ways and for many people it's akin to having good steering feel, or a nice gated shifter, it's another level of driver involvement.
 
Soldato
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Because VROOOOM sounds better than vroom and both sound better than VRRROOOOOM BANGBANGBANGPOPOPOPOPOPOPOBANGBANGPOPOPOP
 
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