LOL, you may have a point there ElAurens.
I believe that this over exaggerated effects have been posted for a different reason - to show the effects what different mixture/throttle/RPM/etc. has on the exhaust. I agree, with a proper mixture setting their visibility in broad daylight should be minimum/non existent - unless when starting an engine (as shown on various videos - well documented). And this can be fine tuned after the process in the engine/cylinder has been properly modeled into the game.