[section9z71]

the black smoke is called soot. its raw fuel. the more black soot. the less air that is going into a cylinder and more fuel.

ever start a fire? see that black smoke that rises off the flame? that is exaclty how the soot escapes from the diesels. the combustion inside the cylinder is so full of fuel compaired to the amount of air, that is pushes the unused fuel out with the combusted fuel.

ever see a diesel first start?..little bit of soot come out. its from the injectors spitting out more fuel into the cylinder then when running, to help start the combustion faster.


when soot escapes from the exhaust, its usually when the engine is under stress/power. when more fuel is needed to haul the wieght.

with tractor pulling diesels. those are pure performance. they never show a sign of environmental health concern haha.
these are just ideas to how it works..

factory diesel..

going into a cylinder:
air-50%
fuel-50%

pushed out the cylinder:

almost clear gases escaping from clean combustion.

chiped diesel..

going into a cylinder:

air-30%
fuel-70%

pushed out the cylinder:

at lower rpms, (where diesels make the most torque) soot pours out. sometimes escaping at 2500 rpms or higher when being pushed

going into a cylinder..

larger turbos, chip, injectors..etc.

air-20%..sometimes less
fuel-80%..sometimes more

pushed out the cylinder:

at any range of rpms, usually a sign of soot. always a large cloud dispensed at lower rpms.


sorry that was such a long post