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My prelude spits flames??
My prelude spits flames??
Just got told im spitting big flames around 7k-8k rpm....overfueling? dumping fuel? its decatted but wasnt expecting flames
- JEBB4
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Mine does this aswell on upshifts and flat down shifts, I put mine down to very poorly mapped "spoon" chip in my ECU combined with decat and full stainless strait through.
I would check your Ecu for a chip
I would check your Ecu for a chip

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- bennyboy
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They all tend to do that after a decat and on the standard ecu as preludes run a little rich. The unburnt fuel hits the hot exhaust and pop.
Mine did it until I had the hondata installed and mapped, then had that extra fuel dialled into extra ponies.
Mine did it until I had the hondata installed and mapped, then had that extra fuel dialled into extra ponies.

Last edited by bennyboy on Mon Nov 23, 2015 8:42 am, edited 1 time in total.
- Merlin
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I have never spat flames, even on my old engine that was untuned (but chipped) with a decat. Spitting flames and pops/bangs can be a sign of poor ignition timing. If too retarded, fuel ignites in the exhaust rather than in the cylinder where it should be.
Easy to sort on a 4th gen - http://www.ludegeneration.co.uk/honda-p ... 11854.html
Easy to sort on a 4th gen - http://www.ludegeneration.co.uk/honda-p ... 11854.html
- vanzep
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@bennyboy is right - almost all 4th gen vtecs will spit flames at top of rev range if they have been decated as they all run rich with standard ecu and even more so with chipped ecu 

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- JEBB4
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Thinking about it now my old B16 civic used to do it with the standard ECU just with a decat and full system, think most of Hondas performance engines are all just set up standard to burn fuel like it's going out of fashion
........... I like that

........... I like that

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- indigolemon
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Actually, if it's a spoon copy chip, it should run leaner, hence the requirement for premium unleaded - you remove the over-fuelling safety net as part of the changes made by the chip.vanzep wrote:... they all run rich with standard ecu and even more so with chipped ecu
'On two occasions I have been asked, 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.' - Charles Babbage