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-   -   Excess Amount of Soot on Tailpipes (https://www.ft86club.com/forums/showthread.php?t=140944)

hpanju 06-15-2020 07:35 PM

Excess Amount of Soot on Tailpipes
 
1 Attachment(s)
Hi guys
Ive been noticing a large amount of soot build up on the inside of my tailpipes. Im running a Stage 2 OFT tune (uel headers, stock air intake) with FT86 UEL headers as well as a Grimmspeed CAI. I know that CAIs can change AFRs, but from the research ive done, the grimmspeed CAI seems to be similar to stock. Am I running too rich, or is this normal? I cleaned and polished my tailpipes about 2 1/2 weeks ago, so the buildup you see in the picture is from 2 1/2 weeks of off and on driving.

humfrz 06-15-2020 07:45 PM

Welp, since it's ma nap time, I'll give you my short answer; soot happens, I suggest you not worry about it.

:)

hpanju 06-15-2020 07:55 PM

Quote:

Originally Posted by humfrz (Post 3341272)
Welp, since it's ma nap time, I'll give you my short answer; soot happens, I suggest you not worry about it.

:)

LOL understood. Just wanted to make sure I'm still within the tolerances, it's my daily and want her to be running for the foreseeable future.

Decep 06-15-2020 07:56 PM

I would say it's normal especially for a canned tune. They're gonna run richer for safety. How are your fuel trims generally?

NoHaveMSG 06-15-2020 08:18 PM

Only way to know is to log it and post the log.

soundman98 06-15-2020 10:44 PM

that's about 1-2 weekends of hard running for me. and i'm stock.

N1rve 06-15-2020 11:13 PM

Normal. My FRS had a lot of soot in the exhaust for some reason. Wayyy more than my M4 for some odd reason.

humfrz 06-15-2020 11:19 PM

Quote:

Originally Posted by hpanju (Post 3341280)
LOL understood. Just wanted to make sure I'm still within the tolerances, it's my daily and want her to be running for the foreseeable future.

Yep, in these modern days, one has to do what the fellows posted up above, to see how rich/lean an engine was running.

Back in the day we could tell by looking at the tail pipe.

no residue - engine hasn't been run

white - running lean

light gray - just right

black - running rich

black with dripping gasoline - choke is stuck closed

Irace86.2.0 06-15-2020 11:58 PM

https://www.caranddriver.com/feature...ect-injection/

Why Are Modern Cars' Tailpipes Often Dirty?

Quote:

According to John Hoard, an associate research scientist in the mechanical engineering department at the University of Michigan, gasoline direct-injection engines, like diesel engines, have a tendency to produce particulate matter, also known as soot. This unfortunate byproduct is a result of direct injection engines' tendency to produce small clusters of rich air/fuel mixture, as well as coat the cylinder walls with liquid gasoline, leading to what are known as pool fires. These conditions are particularly apparent not during aggressive driving but under low load conditions because the intake velocity isn't sufficient to generate the swirling effect needed to effectively mix fuel and air and eliminate any rich areas.

Turdinator 06-16-2020 12:52 AM

Quote:

Originally Posted by hpanju (Post 3341271)
Hi guys
Ive been noticing a large amount of soot build up on the inside of my tailpipes. Im running a Stage 2 OFT tune (uel headers, stock air intake) with FT86 UEL headers as well as a Grimmspeed CAI. I know that CAIs can change AFRs, but from the research ive done, the grimmspeed CAI seems to be similar to stock. Am I running too rich, or is this normal? I cleaned and polished my tailpipes about 2 1/2 weeks ago, so the buildup you see in the picture is from 2 1/2 weeks of off and on driving.

I don't want to be "that guy" but you can literally monitor how rich your car is running with the OFT. No need to guess by the look of your tail pipes.

soundman98 06-16-2020 01:59 AM

Quote:

Originally Posted by humfrz (Post 3341347)
Yep, in these modern days, one has to do what the fellows posted up above, to see how rich/lean an engine was running.

Back in the day we could tell by looking at the tail pipe.

no residue - engine hasn't been run

white - running lean

light gray - just right

black - running rich

black with dripping gasoline - choke is stuck closed

Red - you didn't miss the roadkill by the margin you thought you did!

humfrz 06-16-2020 02:23 AM

Quote:

Originally Posted by soundman98 (Post 3341384)
Red - you didn't miss the roadkill by the margin you thought you did!

Red on the tail pipe? How could you do that .... oh, wait, backing up - :eyebulge:

Brings to mind the time, back on the farm, when I was backing my car out of the barn and ran over the family dog - yep, it was bleeding from the ears and mouth, so, I had to put it down - shot it with my trusty .22 rifle.

The "rest of the story" is that my parents and siblings had gone to Florida for a month, leaving me in charge of the farm (at 14 years old mind you).

Upon their return, after they pulled in the driveway, my little sister bounded out of the car, yelling, "where's Tippy". I told her he was on the other side of the house in the garden. I had buried it and put up a nice wooden marker with it's name on it. My mother glared at me and ask, "what happened to the dog?". I explained. My father asked me if I had killed any other animals on the farm. My sister came from the other side of the house screaming - I hate you!

A lot of thanks from my family for successfully caring for 200 hogs, 14 cows, 8 sheep and 40 chickens, for a month.

:sigh:

humfrz 06-16-2020 02:37 AM

Quote:

Originally Posted by Irace86.2.0 (Post 3341362)
https://www.caranddriver.com/feature...ect-injection/

Why Are Modern Cars' Tailpipes Often Dirty?

So, is that effect offset (at least partially) by the port injection part of the port/direct injection system used by our cars?

humfrz 06-16-2020 02:40 AM

Quote:

Originally Posted by Turdinator (Post 3341367)
I don't want to be "that guy" but you can literally monitor how rich your car is running with the OFT. No need to guess by the look of your tail pipes.

Oh really???

Where have you been Turdinator, I've missed your shitty picture?

:D


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