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first a quick run down of whats going on any help would be great as we have exhasted all options.

its on the dyno getting a tune the A/F perfect 12.0 threw the rev range but just excess fuel black smoke coming out of the exhaust.

now we have changed O2 sensors on the dyno A/F reader also borrowed another one from another tuning shop down the road, both read fine and identical when charts compaired. pulled my car off and put a differnt car on the double check and the sensor is reading perfect.

now there is no power loss and response is great but just excessive black smoke and fumes/fuel you can smell it.

put a brand new O2 sensor in can come out black as f*** also changed plugs after and where realy carboned up.

run down on engine

fully forged

head work

cams tomie b

-5 turbos

pfc pro

z32 afm's

full race twin kotomoto exhaust

dumps

hard piping kit intake and cooler

blitz bovs

hks twin power cdi

yellow jakets coils

800cc sard

tomie reg

044 surge tank

hks cam gears

any ideas would be great cheers

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its twin seperated from the turos right back,

sensor was put in both tail pipes both read identical so this ruled out the first 3 and last 3 cylin runnin differnt

also the exhaust has 02 ports just after dumps, put in both sides up front and same thing reads perfect A/F ratios

its twin seperated from the turos right back,

sensor was put in both tail pipes both read identical so this ruled out the first 3 and last 3 cylin runnin differnt

also the exhaust has 02 ports just after dumps, put in both sides up front and same thing reads perfect A/F ratios

Sounds like super polished combustion chamber - did you specify a combustion chamber suface finish? However if the pulgs are black then I would be looking at the tune. Any chance its really rich on cruise and idle?

only when it get into load the dyno room starts filling up with smoke and fumes

on idle and cruze its fine.

the reason for the retune in the first place is i had some crap go threw my turbos, had the turbo wheels replaced and fitted them backup.

changed the catch can setup from intake sucktion to just atmo filter. also put the blitz bovs on and hks twin power.

when its a full noise and bellowing out black smoke the afr are reading a perfect 12.0 that why its got us stumped. we even wiped the tune and started again but same thing.

super polished combustion chamber why would this cause bellows of black smoke? the head was ported and polished and also the combustion chambers where polished but cant see that being the reson for the smoke.

and i dont mean a little puff of black smoke, it filles the whole dyno room in a power run its that bad. but power is there 375awkw on pump fuel straight up

only when it get into load the dyno room starts filling up with smoke and fumes

on idle and cruze its fine.

the reason for the retune in the first place is i had some crap go threw my turbos, had the turbo wheels replaced and fitted them backup.

changed the catch can setup from intake sucktion to just atmo filter. also put the blitz bovs on and hks twin power.

when its a full noise and bellowing out black smoke the afr are reading a perfect 12.0 that why its got us stumped. we even wiped the tune and started again but same thing.

super polished combustion chamber why would this cause bellows of black smoke? the head was ported and polished and also the combustion chambers where polished but cant see that being the reson for the smoke.

and i dont mean a little puff of black smoke, it filles the whole dyno room in a power run its that bad. but power is there 375awkw on pump fuel straight up

Polished combustion chambers cause less atomisation hence the 12:1 AFR and exess soot. Seen it on many cars with polished combustion chambers. The sards wont give you great atomisation either.

only when it get into load the dyno room starts filling up with smoke and fumes

on idle and cruze its fine.

the reason for the retune in the first place is i had some crap go threw my turbos, had the turbo wheels replaced and fitted them backup.

changed the catch can setup from intake sucktion to just atmo filter. also put the blitz bovs on and hks twin power.

when its a full noise and bellowing out black smoke the afr are reading a perfect 12.0 that why its got us stumped. we even wiped the tune and started again but same thing.

super polished combustion chamber why would this cause bellows of black smoke? the head was ported and polished and also the combustion chambers where polished but cant see that being the reson for the smoke.

and i dont mean a little puff of black smoke, it filles the whole dyno room in a power run its that bad. but power is there 375awkw on pump fuel straight up

12.0 isnt perfect. different for every car. under full load 13 idle 14.7 is a good start.

What else causes black smoke? Everyone tells me my Stagea blows black smoke, but I've had it dyno tuned so it goes ramps up to 11.4:1 up in the revs. Would that be too rich? I have a 100cfm 5" cat, would that have anything to do with it? Sorry for hijacking.

when your turbo's crapped themselves did oil go through ur intercooler? you may have residue oil in there that get pushed up under boost... another thing to check is decel fueling coz if its real rich it takes some time to burn all the excess away. What ECU are you using?

when your turbo's crapped themselves did oil go through ur intercooler? you may have residue oil in there that get pushed up under boost... another thing to check is decel fueling coz if its real rich it takes some time to burn all the excess away. What ECU are you using?

Turbos didnt fully crap themselfs, i was doing some maintance checks and fould my comp wheels abit chewed up, so just had new front wheel put on.

if it was burning oil it wouldnt be black smoke would be blue. also you can smell that it def fuel.

its running a pfc pro

reguards to plugs running .7 gap and not sure what heat range, same as what we have always run tuner has them in bulk lol

What else causes black smoke? Everyone tells me my Stagea blows black smoke, but I've had it dyno tuned so it goes ramps up to 11.4:1 up in the revs. Would that be too rich? I have a 100cfm 5" cat, would that have anything to do with it? Sorry for hijacking.

when you baby it around then only give it stick now and again it blows out all the deposits (condensation and carbon type build up).

when you baby it around then only give it stick now and again it blows out all the deposits (condensation and carbon type build up).

Hmmm that could be it. Gets babied most the time and give it the stick every now then..

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