i have a volvo 850 t5 with turbo back exhaust no centre box cat or restrictions, re map high lift cams think there N/A cams 16t, larger turbo in take pipe and recently a cone filter. the other day my mate was following and he said when i get on boost building speed then change gear flame comes out the exhaust. is this some thing to worry about?? just listed what the car had done as i thought these may cause it to do this? just after advice thanks

 

Nah, that's normal for any car that's running a highflow catless exhaust. When you change gears, the engine runs really really rich for a moment while the engine speed drops and that extra fuel burns in the exhaust causing that flame. My straight piped Camry V6 did that whenever you let off of a hard acceleration. No real problems there.