Posted By RichC on October 10, 2017
Although I’m the last person to criticize folks for tweaking their diesel engines for performance and efficiency, I cringe when I see modifications that purposely over fuel and pump a bunch of black smoke when it is unnecessary (not under load). There has to be a commonsense balance between neutering diesel engines with excessively costly complex systems and “rolling coal.”
Rolling coal is the practice of modifying a diesel engine to increase the amount of fuel entering the engine in order to emit large amounts of black or grey sooty exhaust fumes into the air. It also may include the intentional removal of the particulate filter. Practitioners often additionally modify their vehicles by installing smoke switches and smoke stacks.
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