l love them. Im thinking of getting one for ever now. Just a curious question. When added exhaust etc you ''on certain ones'' get a flame back fire. Are those natural? Or are they custom, such as spark plug etc for the ''effect'' Thanks guys

Definitely custom, and not street legal.

l usually see that happen naturally in mild modified Sti's

if your catalytic converter is removed and you have a straight through muffler, you will get the barking flame, its natural. most cars will do this if you remove the cat. mine shoots out a 2ft flame.

catless exhaust + atmospheric BOV = runs rich, pops & throws flames at every downshift

however, atmospheric bov is r not good for stock/semi stock turbo'd subarus.the previous owner of my car added a BOV, it was 'cool' to shoot flames, but the car ran like crap & l had to remove the BOV

running a bit on the rich side will provide flames every once & a while.but it also has a side effect of washing oil off the cylinder walls

if u see 'rally' cars shooting flames, it is usually due to an anti-lag system used to keep the turbo spooling /building boost

that only happens when your fuel mixture is rich.