What is the definition of "cell" in relation to downpipes?

hokiedood · 09-28-2019, 04:57 AM

Can anyone explain?

Delta0311 · 09-28-2019, 05:28 AM

In scientific terms...

The cell count of a catalytic substrate refers to the number of holes per square inch and is a direct indication of the flow capabilities of that substrate. The lower the count of holes the bigger the hole need to be to fill one square inch, a bigger hole subsequently flows more exhaust gasses.

GtiGyver · 09-28-2019, 08:09 AM

Might also refer to CEL or check engine light. A normal occurrence when swapping in catless downpipes. Performance chips typically clear that problem.

c1pher · 09-28-2019, 08:22 AM

I believe what’s going on is the higher cell count means more holes yes, but also more material to react with exhaust gasses to reduce emissions.

VisualEcho · 09-28-2019, 09:37 AM

CELLS - Literally the little connected boxes inside the converter.
CEL - Check Engine Light

The factory converter has 750 cells, and is therefore more restrictive than the after-market converters, which usually have 200 cells.

A 300 cell converter will not usually cause a check engine light, but all but 1 (Fabspeed) 200 cell converters will cause a check engine light.

09-28-2019, 04:57 AM	#1
hokiedood Private First Class 33 Rep 154 Posts Drives: 2016 BMW 340i Join Date: Feb 2019 Location: San Francisco iTrader: (0) Garage List 2016 BMW 340i [0.00]	What is the definition of "cell" in relation to downpipes? Can anyone explain?
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09-28-2019, 05:28 AM	#2
Delta0311 Banned 7482 Rep 10,119 Posts Drives: 2011 BMW 335xi E92 2016 228xi Join Date: Apr 2009 Location: NJ iTrader: (1)	In scientific terms... The cell count of a catalytic substrate refers to the number of holes per square inch and is a direct indication of the flow capabilities of that substrate. The lower the count of holes the bigger the hole need to be to fill one square inch, a bigger hole subsequently flows more exhaust gasses.
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09-28-2019, 08:09 AM	#3
GtiGyver Lieutenant 71 Rep 462 Posts Drives: 2009 Space Grey E90 328i MT Join Date: Jun 2009 Location: Montreal iTrader: (3)	Might also refer to CEL or check engine light. A normal occurrence when swapping in catless downpipes. Performance chips typically clear that problem.
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09-28-2019, 08:22 AM	#4
c1pher Primo Generalissimo 5018 Rep 4,182 Posts Drives: All of them Join Date: Jun 2009 Location: DC area iTrader: (0) Garage List 2024 Ford Bronco Ra ... [10.00] 2018 Porsche 911 GTS [10.00] 2023 BMW M2 [9.25] 2022 Ford F-250 Tremor [8.50]	I believe what’s going on is the higher cell count means more holes yes, but also more material to react with exhaust gasses to reduce emissions.
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09-28-2019, 09:37 AM	#5
VisualEcho Banned 6657 Rep 4,143 Posts Drives: '18 M2 6MT Join Date: Sep 2019 Location: Missouri iTrader: (1) Garage List 2018 BMW M2 [10.00]	CELLS - Literally the little connected boxes inside the converter. CEL - Check Engine Light The factory converter has 750 cells, and is therefore more restrictive than the after-market converters, which usually have 200 cells. A 300 cell converter will not usually cause a check engine light, but all but 1 (Fabspeed) 200 cell converters will cause a check engine light.
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