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exhaust, just curious

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Old Feb 18, 2012 | 06:38 PM
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exhaust, just curious

When i check out the photo albums of peoples cars on here, i frequently see flames out of the tailpipes. What up with that?
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Old Feb 19, 2012 | 10:50 AM
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Stock ECU cars will tend to spit flames once the emission controls are eliminated and the exhaust is free of cats. The car runs rich momentarily on shifts, dumping fuel into the exhaust.

A proper tune goes a long way to eliminate this, though at high boost levels and rich AFRs needed for those boost levels, you'll still tend to get flames.
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Old Feb 19, 2012 | 07:12 PM
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Ok, not necc gonna get that on an na I guess, lol.
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Old Feb 19, 2012 | 07:16 PM
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You will get that on an N/A ..trust me.
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Old Feb 19, 2012 | 09:33 PM
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Do folks shoot for that kinda thing? Dunno if its really my cup of tea, but what kind of exhaust setup would it take to get the flames from the tailpipe?
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Old Feb 20, 2012 | 12:59 AM
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Originally Posted by whoknows
Do folks shoot for that kinda thing? Dunno if its really my cup of tea, but what kind of exhaust setup would it take to get the flames from the tailpipe?
im nooooot sure on rx7's, but on rx8's, all that is required is to eliminate the cat
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Old Feb 20, 2012 | 02:25 AM
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rx7 full racing beat on an N/A with other light mods and i spit out quick flashes of flames. also run 100 Octane. also flames are cool and all but are cars are to slow for them unless your rocking an FD or built FC.
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Old Feb 20, 2012 | 06:04 AM
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Gotcha. My exhaust is a stock exhaust. I had thought about replacing the cats with straight pipe but i don't know if that will be annoyingly loud or not, pretty much why i havn't done it yet.
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Old Feb 20, 2012 | 09:45 AM
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Im running a straight pipe on my N/A S4, if you could deal with the noise then you'll be fine. Getting on it even a little bit gets pretty loud. Also my car is white so my rear end by the exhaust is starting turn a bit brown from flames.
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Old Feb 20, 2012 | 07:17 PM
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They also used to sell kits to shoot flames from the tailpipe. Part of the whole "Fast and Furious"movement
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Old Feb 21, 2012 | 06:23 AM
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Yeah, im really not much into the whole fast and furious movement. I remember back in old school days some guys would drill and tap their exhaust for spark plugs and wire them to a switch to ignite any extra fuel in the exhaust for flames. I wasn't gonna straight pipe a whole exhaust, just the section for the cats. Would it still be annoyingly loud with just the cats removed but still have the stock mufflers?
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Old Feb 21, 2012 | 07:51 AM
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I dont think it would be too loud without a cat with stock piping. Doesn't stock piping have presilencer(s) on them too? I have 3 inch piping turbo back and its loud as hell. I couldn't stand the raspy high end noise so I put a 3 inch highflow cat. Still super loud, but sounds way better. I previously had stock downpipe (which I think is also a presilencer) 2.x straight piping with a resonator. That wasnt half as loud as my 3 inch piping. Both setups have big large eBay style fart cans.

In other words, I would imagine the smaller stock piping, stock mufflers, and presilencers on your car will still reduce the sound fairly well even without a cat. I never had stock exhaust setup so I cant compare, but maybe this helps a little. Plus from what I read most people here say that the most performance gaining emissions removal is the cat.
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Old Feb 22, 2012 | 12:57 AM
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Flames sound cool hahaha not I wouldnt want to blow my s@!t. I would rather do it right the first time
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Old Feb 22, 2012 | 03:41 PM
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put on a universal high flow cat there not expensive still do some muffling and still keep emissions down
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Old Feb 22, 2012 | 04:34 PM
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yea, like said above you can get a kit to make it do it also, andysautosport.com
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Old Feb 22, 2012 | 05:02 PM
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I've been told that my 86 shot out flames when I was getting on the interstate. The cats are empty and I'm runnung a Apexi dual exhaust with 550cc secondaries. My 10th A/E started backfiring when I installed a no-name single exhaust. It has a downpipe and an empty cat. My moded 91 turbo with a Haltec does not backfire. It has a downpipe, presilencer and Racing Beat dual cat back. They all sound different and I love the sound out of all three.
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Old Feb 22, 2012 | 08:45 PM
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okay guys time to let this thread die.

You remove the cat = flames.

The more fuel your pumping through your system, the more gets dumped and ignited and comes out the exhaust. Its a design flaw of the rotary, it dumps alot of fuel. Thats why our mpg are **** and when you remove the cat its ridiculous.



But worth it!!
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Old Feb 23, 2012 | 09:49 PM
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ok, i got it. Thanks for all the info.
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