Exhaust flames

[spudmn]

Why do the Aussie Touring cars have flames coming out of the exhaust on over run?

The EFI has been programmed to add this extra fuel but what performance advantage is there.

[anonymous-user]

at a guess i think its so there is fuel in the cylinders when htey come back to the throttle?

[awracing]

Valve overlap. the cams and timing setup these cars run mean you get valve overlap (all valves open for a fraction of a second)