Quote:
Originally Posted by SlipBall
I agree, there's something about turbo's that causes a dark smoke after a quick throttle increase...even in todays world with on road vehicles and their modern engines. So I like the idea of the 109 having that behavior  |
Pressure-charging might indeed have a bit increased effect on the smoke puffs during throttle changes. Unless I am mistaken, WW2 planes had only superchargers, not turbochargers.
Combustion during constant RPM is totally different than one during variable RPM. The reason for this is rapidly changing and unequal ratio of fuel and air in the cylinder (variable mixture) - accompanied with black puffs of smoke coming out of the exhaust manifold. Once you set on an desired RPM it takes the engine few seconds to 'stabilize'. Fuel consumption is also much higher during these frequent throttle changes, when compared to running at constant RPM (i.e. just like city / highway driving).
Just like you said - the best example are trucks, when the driver adds power it is always accompanied with thick black smoke coming out of the exhaust. Once it is driving with a constant speed, there is barely any smoke coming out of the exhaust. As far as turbos and truck engines... sometimes it takes up to 2-3 minutes for the exhaust gases to 'stabilize' and spin the turbo for it to have a desired effect.