yo MegOhm's flames look about right, this ain't those funny cars or muscle car stunt shows or old school 3rd - 4th gen jet fighter afterburners.
click in the pix to expand to see the big size
j/k
but you're right, on one patch you could see them during mid day . . . but I felt that seemed a little far fetched b/c I've seen piston (incl spits) start up mid day at the air shows and I barely catch the flames or didn't even see them at all . . .
maybe play with video card settings or in game settings? I remember alot of spec efx in portal 2 weren't showing up until I toyed with the settings.