Vast amounts of black soot from 997.2
#47
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Mine has it as well, not too dramatic, but it shows on the exhaust tips
Absolutely all normal with the engine, temperature, etc., but strange...
Absolutely all normal with the engine, temperature, etc., but strange...
#48
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You definitely have more soot than mine. I can go couple weeks average 200-300 miles, not washing car and still have less soot. I hope you find a solution for it.
John
John
#49
Nordschleife Master
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#50
#51
Nordschleife Master
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http://www.youtube.com/watch?v=_eb8xh4iQ10
i keep trying to take a better sound clip, but everytime i do a full rev clip the wind noise sounds worse... and everytime i get a good one i did "audio only" via the memo recorder on phone and youtube wont upload it..
as far as sound, it takes the best parts from PSE and add's some (think pse with the tube pulled off, so you get that nice burble and the more euro higher pitch)... add the fabspeed center bypass and it made it even louder above 3500/3700 rpms... i really love the sound of the combo i have.. you start it and its louder than usual.. a nice growl.. u can drive around in auto minding your business and not pissing anyone off.. when i have a headache i dont mind it because no drone and not loud unless u get on it.. not even any drone in 7th when i was worried about... you get on it and it sounds sexy as can be.. better than my similar hacked 997.1.... put it in manual mode and decel without downshifting and it spits, and burbles out the back which i find sexy...
ull notice in sound clip about it pops after 1st on accel while cold.. its just all around awesome..
ill try and get more vid's... just gotta figure out how to eliminate wind noise but still get sound..
#53
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This is a great opportunity for one of the chip tuner folks to weigh in with what they have seen- as it would show up in the OE air/fuel ratio maps they reprogram. Are the stock maps super rich? When? Be interesting to see how much the ratio goes past stoichiometric and under what driving conditions.
And if it does, why did the factory make it so rich??? Help cancel out detonation due to the high compression ratios? (a richer mixture will support higher compression ratios as it will dampen detonation) If so, those folks running higher octane would see less soot and those running lower octane more soot.
Rijo- what octane gas do you use? 91? Would be interesting to run a poll by octane used and see if there is a correlation to soot.
I have the awesome good luck to have a nearby station that carries 100 octane unleaded at the pump, and my car runs so much more crisply than using the west coast 91 octane ****-for-gas. Not much soot either.
Conundrum: I don't see how the darn cars pass emissions testing and get such such good gas mileage if it is a A/F richness problem.
#54
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You definitely have more soot than I do. Can certainly understand your aggravation. Will be very curious why this is happening. Sure looks like unburnt fuel to me. Not oil.
This is a great opportunity for one of the chip tuner folks to weigh in with what they have seen- as it would show up in the OE air/fuel ratio maps they reprogram. Are the stock maps super rich? When? Be interesting to see how much the ratio goes past stoichiometric and under what driving conditions.
And if it does, why did the factory make it so rich??? Help cancel out detonation due to the high compression ratios? (a richer mixture will support higher compression ratios as it will dampen detonation) If so, those folks running higher octane would see less soot and those running lower octane more soot.
Rijo- what octane gas do you use? 91? Would be interesting to run a poll by octane used and see if there is a correlation to soot.
I have the awesome good luck to have a nearby station that carries 100 octane unleaded at the pump, and my car runs so much more crisply than using the west coast 91 octane ****-for-gas. Not much soot either.
Conundrum: I don't see how the darn cars pass emissions testing and get such such good gas mileage if it is a A/F richness problem.
This is a great opportunity for one of the chip tuner folks to weigh in with what they have seen- as it would show up in the OE air/fuel ratio maps they reprogram. Are the stock maps super rich? When? Be interesting to see how much the ratio goes past stoichiometric and under what driving conditions.
And if it does, why did the factory make it so rich??? Help cancel out detonation due to the high compression ratios? (a richer mixture will support higher compression ratios as it will dampen detonation) If so, those folks running higher octane would see less soot and those running lower octane more soot.
Rijo- what octane gas do you use? 91? Would be interesting to run a poll by octane used and see if there is a correlation to soot.
I have the awesome good luck to have a nearby station that carries 100 octane unleaded at the pump, and my car runs so much more crisply than using the west coast 91 octane ****-for-gas. Not much soot either.
Conundrum: I don't see how the darn cars pass emissions testing and get such such good gas mileage if it is a A/F richness problem.
7.65/gal=ouch!
#55
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Soot appears to be common on most DFI engines from VW/Audi and BMW also.
The only non-DFI new Porsche is the base 2.9 cayman/boxter.
I recently read an online interview with a main porsche engineer. He said that although all the new 997/987's use the new engine block, they made the the 2.9to get the most out of it without DFI, purposefully. He never elaborated why.
I assume that they wanted the base 2.9's to be non-DFI to help distinguish the higher performance models more. But now I also wonder whether they decided to "play it safe" for other reasons in the base 987 models.
The only non-DFI new Porsche is the base 2.9 cayman/boxter.
I recently read an online interview with a main porsche engineer. He said that although all the new 997/987's use the new engine block, they made the the 2.9to get the most out of it without DFI, purposefully. He never elaborated why.
I assume that they wanted the base 2.9's to be non-DFI to help distinguish the higher performance models more. But now I also wonder whether they decided to "play it safe" for other reasons in the base 987 models.
#57
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Just finished 3 days at PSDS and asked JB about the soot.
A common problem for the 997 DFI cars.
As well oil usage is up by 50%.
Non DFI tips would come back white after hot laps
Not so for the DFI engines.
Pic is 2.5 days of track use at PSDS
A common problem for the 997 DFI cars.
As well oil usage is up by 50%.
Non DFI tips would come back white after hot laps
Not so for the DFI engines.
Pic is 2.5 days of track use at PSDS
#59
Drifting