That is my rx8 shooting flames because I removed the cat
It only happens when WOT and changing gears. Both pics is me shifting around 9k from 3rd to 4th.
Vehicles today tend to run rich because they use more fuel to keep the cat cool so they last longer. By law they have to last 150,000 miles. Anyway so when it is removed, you get flames as I do.
Once the car is tuned they will lean it out a bit and the flames should stop. Which will produce more HP and little better gas MPG.