roadrunner
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posted on 20/11/06 at 09:53 PM |
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pinto backfires
I have a 2ltr pinto with zx9 carbs and megajolt , with the standard mech pump i was getting BIG back fires on over run so , i was told it could be
down to over fueling so fitted zx6 pump but i still have the same problem, i know it could be the timing but how do you time an engine with an ECU,
cheers.
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mookaloid
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posted on 20/11/06 at 10:05 PM |
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sounds like you might need more advance. Backfiring is caused by unburnt fuel igniting out of the combustion chamber on the exhaust side.
This happens when the exhaust side gets too hot as a result of the combustion happening too late in the cycle and the exhaust valve is starting to
open before the combustion process is finished.
It may be over fuelling but more advance would still help.
Sorry no idea how to change the timing with MJ though
Cheers
Mark
"That thing you're thinking - it wont be that."
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PeterW
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posted on 20/11/06 at 11:07 PM |
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quote: Originally posted by roadrunner
I have a 2ltr pinto with zx9 carbs and megajolt , with the standard mech pump i was getting BIG back fires on over run so , i was told it could be
down to over fueling so fitted zx6 pump but i still have the same problem, i know it could be the timing but how do you time an engine with an ECU,
cheers.
Lets have a look at your MJ map - drag it off the ECU and post it as an attachment, or email it to me.
If its not going back past 20BTDC it will have something like this effect.
Are you running MAP or TPS...?
Cheers
Pete
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TangoMan
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posted on 20/11/06 at 11:31 PM |
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Sounds like a mapping issue to me.
I think you need more advance on high vacuum/low throttle openings. Without sufficient advance you will be firing straight down the exhaust on
overrun.
As has been said, post a copy of your map and let us know if it is TPS or MAP.
As I am only down the M180 in Epworth if you come over one weekend I will happily plug the laptop in and tweak it for you.
[Edited on 20/11/06 by TangoMan]
Summer's here!!!!
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tim windmill
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posted on 21/11/06 at 09:46 AM |
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hi brad ,i would also check the inlet manifold and rubbers that attatch carbs to manifold as it could be sucking air in.
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roadrunner
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posted on 21/11/06 at 09:23 PM |
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Hopefully this is the map .
[img]3dmap[/img]
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roadrunner
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posted on 21/11/06 at 09:27 PM |
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Try again , if this does'nt work it's in my archive.
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matt_claydon
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posted on 21/11/06 at 11:52 PM |
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Image
Here you go:
megajolt map
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