Flames on decel
#1
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Excuse the rice question. And yea I know this could be bad for the engine/turbo/rear bumper blah blah, I'm just curious.
I've seen clips and stuff of cars where when they lift off the throttle, there's a fireball/flame that comes out the exhaust. But it's not like those gunshot BMW -10 ignition retard BS or 2-step. It's just a quiet and subtle flame that comes out of the exhaust. What causes this? Super rich overrun? I've gotten my car to just burble and pop here and there but as far as I know, there's no flame. Is it just that the exhaust is so hot, the fuel that gets passed through ignites in the exhaust system during overrun?
Here's a couple of clips of the flames:
https://www.youtube.com/watch?v=gsMP...outu.be&t=1047 - quiet and subtle, maybe cause its a rotary TIME; 17:37
https://www.youtube.com/watch?v=eEvj...outu.be&t=2180 - quiet? Music drowns out TIME: 36:20
I've seen clips and stuff of cars where when they lift off the throttle, there's a fireball/flame that comes out the exhaust. But it's not like those gunshot BMW -10 ignition retard BS or 2-step. It's just a quiet and subtle flame that comes out of the exhaust. What causes this? Super rich overrun? I've gotten my car to just burble and pop here and there but as far as I know, there's no flame. Is it just that the exhaust is so hot, the fuel that gets passed through ignites in the exhaust system during overrun?
Here's a couple of clips of the flames:
https://www.youtube.com/watch?v=gsMP...outu.be&t=1047 - quiet and subtle, maybe cause its a rotary TIME; 17:37
https://www.youtube.com/watch?v=eEvj...outu.be&t=2180 - quiet? Music drowns out TIME: 36:20
Last edited by Spei; 09-25-2020 at 03:06 AM. Reason: Fixed links
#2
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probably depends a lot on your exhaust setup too -- I see 3" but do you have a cat or resonator and what muffler are you running -- or str8 pip3. I would imagine you are on the right track with overrun, but timing retard could definitely make it help too, not necessarily -10 but
tell us more about your setup. Youll get flames either way, either flamed here on the forum, or flames out your tail pipe...... time will tell
tell us more about your setup. Youll get flames either way, either flamed here on the forum, or flames out your tail pipe...... time will tell
#3
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probably depends a lot on your exhaust setup too -- I see 3" but do you have a cat or resonator and what muffler are you running -- or str8 pip3. I would imagine you are on the right track with overrun, but timing retard could definitely make it help too, not necessarily -10 but
tell us more about your setup. Youll get flames either way, either flamed here on the forum, or flames out your tail pipe...... time will tell
tell us more about your setup. Youll get flames either way, either flamed here on the forum, or flames out your tail pipe...... time will tell
#8
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I like pops and bangs, so sue me. I built my car to be cool. Pops and bangs are cool.
spark cut launch/flat shift
spark cut revlimiter
I only turn on overrun under like 2% throttle. So I can de accelerate, give it just a touch of throttle and pop pop balm blam blam.
this combined with natural rumble of big cams sounds badass.
if you want to be an ****, set up a switch to enable spark cut rev limit at like 2k. Rev up and flaaaame ooon.
spark cut launch/flat shift
spark cut revlimiter
I only turn on overrun under like 2% throttle. So I can de accelerate, give it just a touch of throttle and pop pop balm blam blam.
this combined with natural rumble of big cams sounds badass.
if you want to be an ****, set up a switch to enable spark cut rev limit at like 2k. Rev up and flaaaame ooon.
#9
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I like pops and bangs, so sue me. I built my car to be cool. Pops and bangs are cool.
spark cut launch/flat shift
spark cut revlimiter
I only turn on overrun under like 2% throttle. So I can de accelerate, give it just a touch of throttle and pop pop balm blam blam.
this combined with natural rumble of big cams sounds badass.
if you want to be an ****, set up a switch to enable spark cut rev limit at like 2k. Rev up and flaaaame ooon.
spark cut launch/flat shift
spark cut revlimiter
I only turn on overrun under like 2% throttle. So I can de accelerate, give it just a touch of throttle and pop pop balm blam blam.
this combined with natural rumble of big cams sounds badass.
if you want to be an ****, set up a switch to enable spark cut rev limit at like 2k. Rev up and flaaaame ooon.
Ya I've got some pops and bangs on decel. No big flames as far as I can tell. Spark cut sounds nice but I don't think my stock block and turbo like it very much...
#10
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You missed the big one, and it's air.
Hook up one of those old electric emissions pumps to your exhaust and set it to switch on below so much MAP, then fatten the **** out of the low MAP cells. It will flame, pop and bang. Like a SV650 without a marble shoved in the pear....
Or keep your foot on like earlier, or try and tune the MS3 idle valve so it's not retarded.
Hook up one of those old electric emissions pumps to your exhaust and set it to switch on below so much MAP, then fatten the **** out of the low MAP cells. It will flame, pop and bang. Like a SV650 without a marble shoved in the pear....
Or keep your foot on like earlier, or try and tune the MS3 idle valve so it's not retarded.
#11
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
You missed the big one, and it's air.
Hook up one of those old electric emissions pumps to your exhaust and set it to switch on below so much MAP, then fatten the **** out of the low MAP cells. It will flame, pop and bang. Like a SV650 without a marble shoved in the pear....
Or keep your foot on like earlier, or try and tune the MS3 idle valve so it's not retarded.
Hook up one of those old electric emissions pumps to your exhaust and set it to switch on below so much MAP, then fatten the **** out of the low MAP cells. It will flame, pop and bang. Like a SV650 without a marble shoved in the pear....
Or keep your foot on like earlier, or try and tune the MS3 idle valve so it's not retarded.
#19
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I wish I could find the post... It was from several years ago. Someone here did an exhaust system that dumped right around the differential. Melted the whole bumper cover.
#20
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I'm glad I fabbed up my 3" system. My exhaust was dumped right at the diff for serval months...
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