Backfire after spraying
12-31-2011, 11:44 AM
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Staging Lane
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Backfire after spraying Just wanted to see if this is normal...When I spray my 125 wet shot w/ my cutout open, after I'm done and the RPM's are coming down, it sounds like its backfiring and my buddy said flames were coming out. As cool as that might look, I don't think its normal. I'm thinking that its just unsprayed fuel going through the intake, but wouldn't that blow my hood off like some people have done? No window switch btw, only a WOT switch and a flip switch in the cab
Any thoughts?
Any thoughts?
12-31-2011, 11:48 AM
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12-31-2011, 01:54 PM
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Staging Lane
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ok, thats what I was thinkin. But it is bad for the motor at all? I'm thinking its just the extra fumes from the nitrous and fuel being heated up from the exhaust and then it gets ignited and blown out.
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01-05-2012, 09:45 AM
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01-08-2012, 12:16 PM
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01-08-2012, 07:47 PM
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When we were dialing in the nitrous tune on the blazer we had the issue. after reading the plugs and all we ended up leaning it out some. Picked up et and mph. Plugs cleared up and the very same issue you have went away.
So I agree with everyone else. You are running way rich. I even have it on video while we were tuning it and you can hear what you are describing.
during tuning
http://www.youtube.com/watch?v=CRl8S...4&feature=plcp
notice it real good here. That popping was me
http://www.youtube.com/watch?v=YWqY_...6&feature=plcp
and now. Best video I have to show no more popping
http://www.youtube.com/watch?v=pJHu_...eature=related
So I agree with everyone else. You are running way rich. I even have it on video while we were tuning it and you can hear what you are describing.
during tuning
http://www.youtube.com/watch?v=CRl8S...4&feature=plcp
notice it real good here. That popping was me
http://www.youtube.com/watch?v=YWqY_...6&feature=plcp
and now. Best video I have to show no more popping
http://www.youtube.com/watch?v=pJHu_...eature=related
01-10-2012, 07:42 PM
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When you close the throttle and decelerate, the vacuum jumps way up and flash vaporizes the fuel that had puddled on the floor of your intake's plenum.
You know those controversial fuel puddles that are claimed not to exist when using wet systems?
Yep, those very same ones.
The rich misfires causing the popping in your exhaust are just the puddles letting you know what you're in for one day when the vacuum eventually pulls combustion flame back up into your intake.
FYI, most of the factory stock cars/tunes I've tested have the AFR dipping into the 11's already, so no you're really not that far off on average AFR.
The problem with wet systems is that because of very poor fuel distribution, and fuel drop-out, they have to run richer that optimal in order to prevent some lean cylinders.
You could try leaning your wet tune down a bit, and may pick up power and all is well. Be careful and keep an eye on each spark plug and hopefully you will catch any lean cylinders before it is too late.
You know those controversial fuel puddles that are claimed not to exist when using wet systems?
Yep, those very same ones.
The rich misfires causing the popping in your exhaust are just the puddles letting you know what you're in for one day when the vacuum eventually pulls combustion flame back up into your intake.
FYI, most of the factory stock cars/tunes I've tested have the AFR dipping into the 11's already, so no you're really not that far off on average AFR.
The problem with wet systems is that because of very poor fuel distribution, and fuel drop-out, they have to run richer that optimal in order to prevent some lean cylinders.
You could try leaning your wet tune down a bit, and may pick up power and all is well. Be careful and keep an eye on each spark plug and hopefully you will catch any lean cylinders before it is too late.
01-10-2012, 09:07 PM
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Staging Lane
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When you close the throttle and decelerate, the vacuum jumps way up and flash vaporizes the fuel that had puddled on the floor of your intake's plenum.
You know those controversial fuel puddles that are claimed not to exist when using wet systems?
Yep, those very same ones.
The rich misfires causing the popping in your exhaust are just the puddles letting you know what you're in for one day when the vacuum eventually pulls combustion flame back up into your intake.
FYI, most of the factory stock cars/tunes I've tested have the AFR dipping into the 11's already, so no you're really not that far off on average AFR.
The problem with wet systems is that because of very poor fuel distribution, and fuel drop-out, they have to run richer that optimal in order to prevent some lean cylinders.
You could try leaning your wet tune down a bit, and may pick up power and all is well. Be careful and keep an eye on each spark plug and hopefully you will catch any lean cylinders before it is too late.
You know those controversial fuel puddles that are claimed not to exist when using wet systems?
Yep, those very same ones.
The rich misfires causing the popping in your exhaust are just the puddles letting you know what you're in for one day when the vacuum eventually pulls combustion flame back up into your intake.
FYI, most of the factory stock cars/tunes I've tested have the AFR dipping into the 11's already, so no you're really not that far off on average AFR.
The problem with wet systems is that because of very poor fuel distribution, and fuel drop-out, they have to run richer that optimal in order to prevent some lean cylinders.
You could try leaning your wet tune down a bit, and may pick up power and all is well. Be careful and keep an eye on each spark plug and hopefully you will catch any lean cylinders before it is too late.
Instead of tuning, could I maybe step a size down on the fuel pill to lean it out a little bit?