Evo's backfiring/spitting flames

Hey Andre,

Can you explain to me why I've been seeing some evo's circuit racing here in trinidad and lots of flames coming out of the exhaust under braking and downshifting? Is this down to poor tuning per say or is it something that is normal and acceptable?

hey chris

im not andre but to my knowledge it would be either anti lag or deliberate to cool the combustion chamber

hope that helps

It's not anti-lag for sure I know that much.

If you're running a MAf sensor and an atmospheric venting BOV, the engine will be running excessively rich on over run. Particularly on a race track this can result in unburnt fuel igniting and the flames you're noticing. Alternatively it's also common to purposely tune the engine rich on over run to help cool the engine.