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Super Modulator
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It's a beautiful setup, to be sure.

As I recall the twincharging permitted the 1.7L engine to compete with the larger 2.1L engines in power, but the lower displacement allowed >100kg chassis weight reduction by regulation.
 

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Super Moderator (Actually a SuperSpy)
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Yes. Because they elected to stay below 1,8L displacement, they took advantage of the "multiplier" in the rules for max weight and the chassis could (I think) weigh less than 1000kg. This means they could have roughly 500HP (who's counting?) for a chassis that weighed less than 1 ton.

The plastic snout with engulfed fixtures was a result of relatively late development work to solve some aero problems. Earlier evolutions used a "road style" nose but I am only able to find the classic press photo featuring Henri Toivonen and Markku Alén from the Group B version's introduction.



A very long time ago, on Usenet, I ended up in a discussion with a Pirelli man who confirmed my suspicion that the Stradale (civilian, non-Group-B) version of the δ S4 was the car on which the P Zero was introduced. I recalled a very early press event with Sandro Nanini at the wheel of a civilian S4 fitted with the then-revolutionary, asymmetrical tread PZero.

Time flies.
 

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Super Modulator
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We didn't address the crux of OP's amazing question.

What permitted the S4 to shoot 1m flames from the tailpipe?

Was it the anti-lag system, unburned fuel vapors, or merely the exceptionally short exhaust path?
 

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Super Moderator (Actually a SuperSpy)
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The "antilag" they implemented was merely the use of the Volumex to keep the engine boosted at low RPM while the turbo had a chance to spin up. The engine was apparently always under boost, from idle to redline. Unburnt vapours did the trick as far as I can work out. I can't work out how, or if, they relieved pressure between gears. I seem to remember dump valves not being used, and the banging in this case would then be the turbine clanking against its own pressure wave. The exhaust path can be measured in cm, true, but even the Audi (a van in comparison, with the engine as poorly placed in the chassis as Subaru does to this day and much longer exhaust) would shoot 1m+ flames and that car was the size of a barge.

Incidentally, my IP is also outside Los Angeles, just like OP's! (And no, I'm not OP; I've taken it upon myself to neither answer such "flaming car anus, how do I do it" questions nor take them seriously though).

I used to think Fast/furious movies were moronic but nowadays I like them a lot less. I'd not be seen dead in a cinema showing that drivel. I don't go to "meets" because Brosephs will show up with huge wings and silly trousers, and I'm just too snooty and haughty for all that. Luckily I'm extremely good looking so I can get away with a whole lot of attitude though. Life's great!
 

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Super Moderator (Actually a SuperSpy)
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Friendly Neighborhood Spider-Admin
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My somewhat-modded Beetle (dual carbs, better ignition, etc) would shoot a flame here and there, if I revved it up a bit and suddenly let off the gas. Not even remotely quick by modern standards, but it sounded great and flame emitted from a stinger pipe was awesome. I miss my air-cooled's...
 

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BooSTIng
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2,594 Posts
Ok, I guess I will contribute assuming this guy is being serious.

The most common way to "shoot flames" is what they call afterfire. This is caused by a very rich air/fuel mixture that is not burnt off during combustion causing the unburned fuel to ignite in the exhaust, thus causing a flame to shoot out of the exhaust.
 

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Master linguitist
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10,036 Posts
Wire in an ignition cut on a button, wire in sparkplugs to the tail pipe and put them in the ignition. Fire it up, floor it then hit the ignition cut and let it go and mash the gas pedal. Then let go of the ignition cut and mash the gas again. Flame throwers, also jail time.

Don't expect anything to last very long.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

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Super Modulator
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On a totally serious note, do you think we could rig my pants to shoot flames when I let pass?
 

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Master linguitist
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Should we use a fiberglass heatshield so it moves, but causes glass splinters in the perineum or use a rigid titanium one?

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

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