Dual exhausts? everywhere, but not on the right cars

TheCleaner

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Newcastle, England
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2004 Clio dCi 1.5 100HP
Its just something I've noticed which I can't understand. Now from a design perspective, dual exhaust (outlets on both sides) do balance the back out and give a sportier look that tends to differenciate higher models from low ones, but there are some makers what make their higher models not stand out enough, while at the same time putting it on lowly models.

Example of Audi.
The new RS3, the top sport model for the range, single side twin exhaust that you would get on the base 2l TDI model....
8AudiRS3Sportbackreviewpictures.jpg


Yet on the A4's, the 1.8 even got dual exhausts, balancing the back out and giving a bit more of a sporty look.. surely an RS car deserves at least that.
2002_a4_1.8t.jpg


and even the diesel gets the dual treatment
car_photo_219067_7.jpg


Now thats where I cant understand the reasoning other than marketing because I feel BMW understate the better cars so that a 330i looks no different to a 32Xi and 'unsportier' to their competition audi's, yes the 335i gets the dual finally, but then you move to the 5 series where there is a V8 model 545/550i's which have no differing exhaust to the 520i? is that just being cheap, surely a v config is good reasoning and something to put under the quad exhaust M5 which looks stunning.

If nothing it probably proves they're next to useless in terms of performance, but some design decisions just baffle me.

And taking the cake for pointlessness/marketing, the fiat 500 abart and suzuki swift sport, 1.4l and 1.6l straigh 4's respectively...
fiat-500-abarth-right-rear-quarterpanel.jpg
suzuki_swift_sport_rear_05_09_06.jpg


I would say though, even worse than these are those manufacturer that give a car dual exhausts that dont need it, only to then hide them behind the rear bumper. I've seen a few modeo TDCis like this which have straight-4s and no reason I can think of at all.

This is just a rant thread but are there any more pointless dual exhausts on cars you know of, or car that should have them but dont (like RS3, V-config engined cars)
 
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Could be any number of technical reasons - size of the differentials, prop-shafts, depth of the spare wheel well, size of the fuel tank required, all limiting where the space is underneath.
 
TheCleaner, never ever look at the GMC Acadia or you'll have a heart attack. Quad exhausts on a bloated crossover vehicle.
 
Technically, they're not really dual exhaust, but I know what you mean.

I personally hate those type of dual outlets, unless they're on a car with a V engine. It just seems fake; like you're trying to make everyone think, "Ooh, look at those dual pipes - he must have a powerful V6 or V8 in there." I blame Honda. Before the S2000 came along, no one would have thought of putting a dual-looking exhaust on a I-4. (Well, okay, the 2nd gen Toyota MR2; but they didn't call attention to it by putting big chrome tips on it like Honda did.) Now it's gotten to the point where the Miata - a car that to me symbolized the pure modern sports car - has them.

As for cars that didn't have them but should, the only one that immediately comes to mind was the LS1 powered Holden Monaro/Vauxhall VX-R/Pontiac GTO.

https://pic.armedcats.net/p/ph/phoenixsac/2011/06/15/2004-pontiac-gto-2-door-coupe-rear-exterior-view_100262448_m.jpg
 
Balancing out the back? Looks-wise maybe, but not from a dynamic standpoint. What irks me is single cylinder bank cars with dual exhausts; so pointless.

Yeah i meant looks wise, which lets face it, looks sell, as does a bit of uniqueness (something to show that your debadged 550i is the big V8 without having to badge it as such, and anoraks like us can give a nod of approval) That why its strange when manufacturers dont really show that its a better, more expensive model in the looks. And I agree full on the single bank cars, as pointed out by the 500 and swift.
 
Technically, they're not really dual exhaust, but I know what you mean.

Depends, some are, although they usually have a crossover I guess.
 
But not on an inline four - or six, for that matter. A true dual exhaust has a set of pipes coming from each cylinder bank.
 
The back of my Legacy:

Leg08SEsilverrear1.JPG


My 2.5 flat four does not need dual exhaust. I actually wish it was a single, the 2.2 flat four in my older Legacy sounds throatier than the new 2.5.

Even my parents' Hyundai Santa Fe has it, it is completely overdone.

Also, here is the Volvo C30 with its 5 cylinder engine and dual exhausts :blink: :

volvo-c30.jpg
 
Balancing out the back? Looks-wise maybe, but not from a dynamic standpoint. What irks me is single cylinder bank cars with dual exhausts; so pointless.

Yep, never understood the point of a dual exhaust on my car its an inline 4 banger....
 
Even though I get the whole "it's just a 4 cylinder" thing, I much prefer the look of two smaller exhaust pipes than one large 3" one on FI cars.
 
The reason it's not an technical advantage for a car to have as many exhausts from front to back as cylinders is that the gasses coming at different times, according to the firing order, keep a constant flow in the pipes, whereas in a single pipe the flow would be interrupted and restarted constantly, which costs power.

This, and packaging, cost etc. is the reason that most 4 cyl. cars have just one pipe to the back, splitting again if two pipes are wanted (which has no technical use).
 
My 2.5 flat four does not need dual exhaust. I actually wish it was a single, the 2.2 flat four in my older Legacy sounds throatier than the new 2.5.

Actually, being a horizontally-opposed engine, it could use a dual exhaust system - with a set of pipes for each bank of cylinders.

https://pic.armedcats.net/p/ph/phoenixsac/2011/06/15/0466.gif

However, as it's not a racing or performance car, you're right; it doesn't need them. And it's not a true dual setup anyway; it's just a Y pipe either in front of or just behind the rear axle. Ironically, that's the type of exhaust I had on my V8 Thunderbird: a catalytic converter attached to each manifold, then a single pipe running down the center to a third cat; and finally a Y-pipe in front of the rear axle branching out to dual mufflers just behind the rear wheels.
 
Why don't more exhausts use DEI, that's the real puzzle.
 
What irks me is single cylinder bank cars with dual exhausts; so pointless.

No. My L6 Jag has two exhausts. Each one traces back to either the three back or three front cylinders (the gases from either bank never meet). If they only wanted to show off they wouldn't have gone through that much effort.

Exhaust optimizing isn't as simple as "one bank, one pipe".
 
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Technically, they're not really dual exhaust, but I know what you mean.

I personally hate those type of dual outlets, unless they're on a car with a V engine. It just seems fake; like you're trying to make everyone think, "Ooh, look at those dual pipes - he must have a powerful V6 or V8 in there." I blame Honda. Before the S2000 came along, no one would have thought of putting a dual-looking exhaust on a I-4. (Well, okay, the 2nd gen Toyota MR2; but they didn't call attention to it by putting big chrome tips on it like Honda did.) Now it's gotten to the point where the Miata - a car that to me symbolized the pure modern sports car - has them.

As for cars that didn't have them but should, the only one that immediately comes to mind was the LS1 powered Holden Monaro/Vauxhall VX-R/Pontiac GTO.

https://pic.armedcats.net/p/ph/phoe...door-coupe-rear-exterior-view_100262448_m.jpg

Fun Fact, the LS1 GTO's had a true dual exhaust, they just exited on the same side right next to each other.

https://pic.armedcats.net/t/to/tomcat/2010/12/17/pontiacgtoinsides4.jpg
 
I see nothing wrong with that. Obviously it is not as nice looking as a split at the rear, but it is a dual exhaust.
 
I see nothing wrong with that. Obviously it is not as nice looking as a split at the rear, but it is a dual exhaust.

One side is longer than the other so I would assume that each bank is running slightly differently. Additionally I don't understand the point of this set up, it would be much simpler to run the exhausts in mirrored configuration.
 
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