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Discussion Starter · #1 ·
im just curious if it has happened with our cars. because its fairly easy w/ rx7s and supras. how bout us???

god, with all thats done w/ your car, w/ the new injectors, no cats, etc etc....are you blowing flames between shifts? heh
 

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blame it on the five alarm chili:D
 

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(free bump!) i honestly doubt u can blow flames w/ a wrx, at least with anything close to stock, but i wanna hear what other ppl think
 

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Discussion Starter · #4 ·
heh, im not tryign to be sarcastic. im really curious

if rx7s and supras can do it stock w/ no cats

i dont see why we cant do it w/o cats and upgraded turbos and ish
 

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Yes you can. Just look at the Factory Forced Induction Forum on i-Club, Imprezer goes into detail about shooting fireballs.

John
 

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Mario,

Catless cars "shoot out" small launch fireballs. Race cars do it all the time, especially when they shift.

Here's what happens:
Under full throttle, a well-tuned car runs a tad rich. When you let off the gas quickly, the car goes lean immediately.
Think of unburned fuel in the pipe and then hot air added right behind it.
This can result in "backfiring" in the pipe, where the fire starts and burns itself out immediately, (not good in a passenger car)

BUT.... if you maintain exhaust velocity via ideal pipe diameter, the gases will follow each other and won't mix until the end of the pipe (tail pipe) where you get a rapid expansion and immediate mix of the fuel and the hot air (also the cooler ambient air.)

-Jim
 

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On Sunday afternoons I've caught Le Mans on TV. There is a white and blue BMW M3 that spits fire out of its side exhaust pipe all the time. I've heard it's very bad for your injectors.

I swear The F&F movie really failed terribly in some areas. "Dude, I need Naaaaawwws".

-- Rich
 

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A little OT, but... Probably the scaredest I've ever been was while teaching a motorcycle class on base in Augusta, GA. I was passing a late model camaro that backfired so loudly I thought I had died (actually, thought I had been shot). It was about 15 feet away from me when it happened. I couldn't hear out of my right ear for a good 30 minutes.
 

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Any body remembe the beautiful, flat-torque curve, ~450HP, black, Mitsubishi, in Sport Compact Car about five months ago. That had a seperate wastegate pipe that exitted in the wheel wheel and shot flames if you pumped the throttle from a dead stop. They said something like, "Very few cars have the unique characterstics of this car, like flames shooting out of the wheel well at a stop light."

Very cool and at the same time DANGEROUS. Plus, I don't think I'd race a car that did that! :D

-Jim
 

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you know what IS cool though, is those auto-deterrents (not really deterrents...hehe) that attach to the underside of your car and shoot flames out from under your car at anyone trying to break in. you'll never have to worry about you car getting stolen, unless the guy feels like breaking in while he's on fire
 

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if ur exhaust temp is close to or above 800, a few idle revs u'll get the fire, if u' have a 100% blow off, u get more fire, but might stall due to the 100% blow off
 

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I've blown a few light flames/sparks out of my car before, my setup at the time was:

HKS Downpipe
HKS Hi-Power Catback
Gruppe-S Uppipe (catless)
HKS 100% SSQV BOV

They only happened when i dropped my car into 3rd and gunned it to redline and slammed 4th quick, then there would be a light flame/spark. But i don't do that anymore :D
 

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EVO's can shoot flames very well. Jim has a video my friend (wrxwookiees) took on his site from summit point. Mach V's EVO was shooting a flame for about 2 seconds, it was sweet.
 

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"Here's what happens:
Under full throttle, a well-tuned car runs a tad rich. When you let off the gas quickly, the car goes lean immediately.
Think of unburned fuel in the pipe and then hot air added right behind it.
This can result in "backfiring" in the pipe, where the fire starts and burns itself out immediately, (not good in a passenger car)"

From what I know, it is actually the opposite. Catless wrx's with 100% atmospheric bovs shoot flames. This is cause when the bov opens, the air which has been measured by the maf is let out, and since enough gas is sent for the air that is still in the manifold, and the air that has escaped, the mixture becomes very rich... The unbernt gasses ignite and shoot flames if the explosion is big enough.......... Obviously this will happen more often with wrx's which the a/f ratio hasn't been tuned or is still running on the stock ecu, and run richer more often.

One example would just be a catless wrx with a 100%bov being the only mods. If someone drove this car at wot near redline, then let the pedal up, the car would shoot a flame because the ecu already had the a/f mixture really rich since the car was running at wot near redline, then the bov let off air making the mixture even richer while lowering the rpms quickly.....kaboom...
 

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I have been catless for about 400 miles and one auto-x, still no CEL (knock on wood). I do have a little leak though at the Turbo/Downpipe Flange, that will be fixed with a new Subaru Gasket in a week.
 
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