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Discussion Starter #1
after doing some hard runs, I'll notice black residue accumulate around the rear of my car, all over the bumper, around my right rear tire area. I'm checking the tailpipe, no carbon build up. I'm thinking it might be my sucky ass tires. I don't see any smoke, I've had someone watch as I mash down. At WOT i'm running 11.9 -11.6, thats not rich..
ideas?
 

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Discussion Starter #3
not an idiot NiNE.. i feel like an idiot asking but.. u could be right.. its a fine dust/residue. i can take it off with those dusters.. when you run hard do you see stuff on the rear portion of your ride?
 

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yes compared to a 14.7

remeber just casue your boosted doesn't change chemestry

12 air molecules to each fuel molecule - so there is going to be more fuel molecule than necessary when stoiciometric combustrion ocurs at 14.7 air molecules to 1 fuel molecule.
 

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somguy2u said:
yes compared to a 14.7

remeber just casue your boosted doesn't change chemestry

12 air molecules to each fuel molecule - so there is going to be more fuel molecule than necessary when stoiciometric combustrion ocurs at 14.7 air molecules to 1 fuel molecule.
I've just been skooled :lol:
 

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rear bumper section above my exhaust is also black :)

i make sure i clean it every now and then
 

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somguy2u said:
unspent fuel more than likely - running a lot richer with the boost
^^^yeah what he said...
 

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i get a black residue on my back bumper aswell, but i've noticed it on other cars i've had too. i havent put to much thought into it other than road dust. do you have the same residue on the sides of the back bumper and sides of the car where the wheels are?
 

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im pretty sure aftermarket y-pipes cause this problem.
 

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theformat26 said:
im pretty sure aftermarket y-pipes cause this problem.
Hahah. WTF?
After reading this thread I didn't even find a problem.
Your response has me sitting here trying to finger out what I'm not understanding.
 

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im just saying what i was told a while ago. I was asking someone about if i shuold put the y-pipe on or not, and they told me eventually, the rear end of my car would develop a lot of black residue i guess you can call it. maybe cause there is no catalytic converter? im not sure.

i could be horribly wrong :bigSmile:
 

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Even when I was stock, after a few days of driving the car, I'd get heavy dust on my back bumper. From what I've heard, it was just the aerodynamics of the car. The way the air swirls behind the car, it takes all the debris and deposits it right on my bumper shelf. I'ts been doing it since day one, so I can't see it being related to any of my mods.

Maybe its just good ol' southern californian road polution :lol:
 

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theformat26 said:
im just saying what i was told a while ago. I was asking someone about if i shuold put the y-pipe on or not, and they told me eventually, the rear end of my car would develop a lot of black residue i guess you can call it. maybe cause there is no catalytic converter? im not sure.

i could be horribly wrong :bigSmile:

I think what the person who told you that meant was there would be resedue coming from the tailpipe, and he said that he didn't see any buildup by his tailpipe. ionno :confused:
 

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unsubscribing from this thread.
always more important issues than dust.
 

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Discussion Starter #17
NiNE said:
i get a black residue on my back bumper aswell, but i've noticed it on other cars i've had too. i havent put to much thought into it other than road dust. do you have the same residue on the sides of the back bumper and sides of the car where the wheels are?
Yup.. guess I'm being too paranoid. :confused:

somguy2u said:
yes compared to a 14.7

remeber just casue your boosted doesn't change chemestry

12 air molecules to each fuel molecule - so there is going to be more fuel molecule than necessary when stoiciometric combustrion ocurs at 14.7 air molecules to 1 fuel molecule.
thanks for the info :)
 

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It's more than likely unspent fuel... I had this problem all the time running my old turboeast emanage setup... There is nothing wrong with your car... Just make sure you look underneath... no trans fluid or oil on the bottom, then its most likely fuel... A trip to the car wash solves this problem. When I went standalone, it seemed to cure alot of this problem... but now its dust from the burnt tires on the back...
 
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