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Flames from exhaust??

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Old 11-03-05, 08:32 PM
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Question Flames from exhaust??

Why exactly does this happen on our cars?

Im rebuilding - my 90 GTU N/A

And will this happen with my car

It happens on my friend Chris's t2
Just wondering
Old 11-03-05, 08:40 PM
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With a straight pipe yes.
Old 11-03-05, 08:44 PM
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he has apexi n1's
Old 11-03-05, 08:44 PM
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[B]flames rock!!
Old 11-03-05, 09:06 PM
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yes, with no converters it will do it, but i still cant make mine do it reliably when i want it to, it just kinda does when it wants.
Old 11-03-05, 09:07 PM
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I wanna go BRAP BRAP BRAP BRAP BRAP...
Old 11-03-05, 09:20 PM
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missed it the first time. it happens due to port overlap, which causes blowby...in other words, some of the intake charge just shoots right through the engine, so when it comes out the exhaust very hot and hits air (oxygen) it burns, hence flames.
Old 11-03-05, 10:32 PM
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Also, the fact that under most operating conditions the stock ECU runs the engine really rather rich, leading to unburned fuel, and the fact that the long moving combustion chamber isn't exactly great for keeping everything lit, and there's a lot of quench area to keep fuel from burning completely.

Basically, a good quantity of unburned gas gets kicked out under many conditions.

Patman, wouldn't intake charge going into the exhaust burn immediately upon hitting something hot? It has a good fuel/air mixture. The rich mixture is what's really responsible - there is no more oxygen to burn until it gets to the end of the tailpipe. Also, people with well tuned standalones seldom shoot flames, even with engines that have significantly greater overlap.

-=Russ=-
Old 11-03-05, 10:37 PM
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i blow flames all the time....
its the stupid stock ECU and our worn out TPS... and unworking acv and noe missions!
Old 11-04-05, 02:45 AM
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aw man my microtech wont let me shoot flames.
Old 11-04-05, 11:13 AM
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Whats a microtech?
Old 11-04-05, 11:23 AM
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microtech= brand of standalone ems

aw man my microtech wont let me shoot flames.
functions>options>MixTrim. +15% or so. your car will run like ***, but you'll make some flames. you gotta play with the mixture some to get it right.
Old 11-04-05, 11:51 AM
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I just hit the 2-step!
Old 11-04-05, 01:10 PM
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Originally Posted by J-Rat
I just hit the 2-step!
ditto.

Old 11-04-05, 02:08 PM
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Originally Posted by ducktape
ditto.

dam son, whats your car drinkin? 151?
Old 11-04-05, 03:02 PM
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So then i will be able to do this in my n/a - fc if i remove emmisions and set up a straight pipe?

Oh and should i set it up as a single or duel exhaust?
Old 11-04-05, 03:20 PM
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Ok bud.... looky here.... Yes.. If you remove your emissions...

But.. look at those pics... its not something you do by revving the engine to 3 grand....

you gotta be hammering it......

As far as the mictro tech not letting you blow flames?? WTF?? why not??? Is the decel cut in that thing automatic???
Old 11-04-05, 03:22 PM
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Originally Posted by J-Rat
I just hit the 2-step!
you got a 2-step????? tell us more!!!!!
Old 11-04-05, 04:01 PM
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Originally Posted by YearsOfDecay
you got a 2-step????? tell us more!!!!!
All Haltechs/microtechs/etc have 2-steps. ITs part of the ECU.
Old 11-04-05, 04:08 PM
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i have a full racing beat exhaust on my car (road race header, 2 pre-silencers, 2 mufflers) and my baby shoots flames when i downshift and get on it, or when i rev it up to 6k and feather the throttle rappidly. only works when the pipes are nice and warm though.
Old 11-04-05, 04:18 PM
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BLACK LABEL--why do you have 2 presilencers??
just wondering if its for emmissions or whatever

Last edited by hondaslaya; 11-04-05 at 04:19 PM. Reason: content
Old 11-04-05, 05:56 PM
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my revcut is set at 9250. no way am i gonna hit in on purpose just to make some flames.
Old 11-04-05, 09:48 PM
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Originally Posted by patman
my revcut is set at 9250. no way am i gonna hit in on purpose just to make some flames.
I have one at 9k, and a toggle-able one at 4k. :P
Old 11-08-05, 08:48 AM
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Originally Posted by J-Rat
All Haltechs/microtechs/etc have 2-steps. ITs part of the ECU.

OH.. your talkin about the ignition cut in the haltech itself......

I thought you had a seprate 2-step box on the ignition module to keep the RPMS at say, 4500, as the lights were comming down the tree....
Old 11-08-05, 08:49 AM
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The haltech has a 2-stage ignition cut.. I hold a button and my haltech cuts the ignition at 5000, and when I release the button my rev cut goes to 8200. Thats a 2-step.

Rat


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